`CVE-2023-38545`

Affected software	4 products, listed below
Severity	9.8 Critical CVSS 3.1 2 scores
Weakness	Out-of-bounds write (CWE-787)
Published	18 Oct 2023
Updated	17 Jun 2026

Description

This flaw makes curl overflow a heap based buffer in the SOCKS5 proxy handshake. When curl is asked to pass along the host name to the SOCKS5 proxy to allow that to resolve the address instead of it getting done by curl itself, the maximum length that host name can be is 255 bytes. If the host name is detected to be longer, curl switches to local name resolving and instead passes on the resolved address only. Due to this bug, the local variable that means "let the host resolve the name" could get the wrong value during a slow SOCKS5 handshake, and contrary to the intention, copy the too long host name to the target buffer instead of copying just the resolved address there. The target buffer being a heap based buffer, and the host name coming from the URL that curl has been told to operate with.

Exploitation status

Proof of concept only

A proof of concept exists, but no reviewed exploit catalogue lists this CVE.

CISA KEV not listed
VulnCheck KEV not listed
CISA Vulnrichment exploitation: poc CISA recorded that an exploit has been demonstrated. Automatable: no, technical impact: total.
Indexed PoC 7 indexed Published artifacts you can open, in GitHub PoC; first seen 2023-10-11.
EPSS 78% chance in 30 days A model's forecast, not a report of exploitation. Higher than 99.6% of all scored CVEs.

3 of these are GitHub repositories with fewer than 5 stars. They are listed for reference and don't count toward the exploitation status above.

Index	Artifact	Stars	First seen
GitHub PoC	This script is designed to exploit a heap buffer overflow vulnerability in a socks5 proxy server.	21	2023-10-17
GitHub PoC	Simple PoC causing overflow	20	2023-10-11
GitHub PoC	😄 CVE-2023-38545堆溢出的POC和分析文章	8	2023-10-12
GitHub PoC	Simple PoC causing overflow	6	2023-10-12
GitHub PoC	A proof of concept for testing CVE-2023-38545 against local curl	4	2023-10-16
GitHub PoC	Dockerfile containing all the necessary setup files to demo the exploit	3	2023-10-12
GitHub PoC	CVE-2023-38545 POC for the curl command line tool	2	2023-10-16

Waratek protection

Outside Waratek scope

A Java vulnerability, but not one Waratek protects. It affects only Java on a user's desktop (applets, Web Start, JavaFX, the installer), sits in a product the Waratek agent can't be installed into, or is in a package we don't expect in business applications. The decision below says which.

Protection none
Action not pursued none
Review human Researcher
Record active

Decided by	Manual classification of this CVE in the legacy dataset
Finding	A manual classification set this CVE's status to Outside Waratek scope, but the CVE names a tracked product.

Decided by

Manual classification of this CVE in the legacy dataset

Finding

A manual classification set this CVE's status to Outside Waratek scope, but the CVE names a tracked product.

CVSS

9.8 CRITICAL v3.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H 2 metrics

We show the highest score from the newest CVSS version. Scores from different versions can't be compared, and the first score listed is sometimes a 0.0 placeholder.

Version Score Band Vector Assigner Type

CVSS 3.1 9.8 CRITICAL CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H NVD Primary published

CVSS 3.1 8.8 HIGH CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H CISA-ADP Secondary

Version	Score	Band	Vector	Assigner	Type
CVSS 3.1	9.8	CRITICAL	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`	NVD	Primary	published
CVSS 3.1	8.8	HIGH	`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H`	CISA-ADP	Secondary

Affected software and releases

Oracle advisories

Advisory	Type	Quarter	Products Oracle names in its risk matrix
Oracle Critical Patch Update October 2024 ↗	CPU	2024-Q4	Oracle Analytics / Analytics Server (curl) (7.0.0.0.0, 7.6.0.0.0, 12.2.1.4.0)
Oracle Critical Patch Update April 2024 ↗	CPU	2024-Q2	Oracle PeopleSoft / File Processing (curl) (8.59, 8.60, 8.61)
Oracle Critical Patch Update January 2024 ↗	CPU	2024-Q1	Oracle Database Server / Oracle Spatial and Graph (curl) (19.3-19.21, 21.3-21.12, 23.3) Oracle Essbase / Essbase Web Platform (curl) (21.5.3.0.0) Oracle Fusion Middleware / Third Party (curl) (12.2.1.4.0) Oracle MySQL / Cluster: General (curl) (8.0.34 and prior, 8.1.0)
Oracle Critical Patch Update October 2023 ↗	CPU	2023-Q4	Oracle MySQL / Server: Compiling (curl) (5.7.43 and prior, 8.0.34 and prior, 8.1.0)

Advisory

Type

Quarter

Products Oracle names in its risk matrix

Oracle Critical Patch Update October 2024 ↗

CPU

2024-Q4

Oracle Analytics / Analytics Server (curl) (7.0.0.0.0, 7.6.0.0.0, 12.2.1.4.0)

Oracle Critical Patch Update April 2024 ↗

CPU

2024-Q2

Oracle PeopleSoft / File Processing (curl) (8.59, 8.60, 8.61)

Oracle Critical Patch Update January 2024 ↗

CPU

2024-Q1

Oracle Database Server / Oracle Spatial and Graph (curl) (19.3-19.21, 21.3-21.12, 23.3)
Oracle Essbase / Essbase Web Platform (curl) (21.5.3.0.0)
Oracle Fusion Middleware / Third Party (curl) (12.2.1.4.0)
Oracle MySQL / Cluster: General (curl) (8.0.34 and prior, 8.1.0)

Oracle Critical Patch Update October 2023 ↗

CPU

2023-Q4

Oracle MySQL / Server: Compiling (curl) (5.7.43 and prior, 8.0.34 and prior, 8.1.0)

Oracle components and versions

Family	Component	Versions, as Oracle lists them	Read as
Oracle Analytics	Analytics Server (curl)	7.0.0.0.0, 7.6.0.0.0, 12.2.1.4.0	7.0.0.0.0 · 7.6.0.0.0 · 12.2.1.4.0
Oracle Database Server	Oracle Spatial and Graph (curl)	19.3-19.21, 21.3-21.12, 23.3	23.3
Oracle Essbase	Essbase Web Platform (curl)	21.5.3.0.0	21.5.3.0.0
Oracle Fusion Middleware	Third Party (curl)	12.2.1.4.0	12.2.1.4.0
Oracle MySQL	Cluster: General (curl)	8.0.34 and prior, 8.1.0	8.1.0
Oracle MySQL	Server: Compiling (curl)	5.7.43 and prior, 8.0.34 and prior, 8.1.0	8.1.0
Oracle PeopleSoft	File Processing (curl)	8.59, 8.60, 8.61	8.59 · 8.60 · 8.61

Family

Component

Versions, as Oracle lists them

Read as

Oracle Analytics

Analytics Server (curl)

7.0.0.0.0, 7.6.0.0.0, 12.2.1.4.0

7.0.0.0.0 · 7.6.0.0.0 · 12.2.1.4.0

Oracle Database Server

Oracle Spatial and Graph (curl)

19.3-19.21, 21.3-21.12, 23.3

23.3

Oracle Essbase

Essbase Web Platform (curl)

21.5.3.0.0

Oracle Fusion Middleware

Third Party (curl)

12.2.1.4.0

Oracle MySQL

Cluster: General (curl)

8.0.34 and prior, 8.1.0

8.1.0

Oracle MySQL

Server: Compiling (curl)

5.7.43 and prior, 8.0.34 and prior, 8.1.0

8.1.0

Oracle PeopleSoft

File Processing (curl)

8.59, 8.60, 8.61

8.59 · 8.60 · 8.61

Products and versions

13 products, 13 version entries

Source	Vendor	Product	Scheme	Affected versions
nvd	fedoraproject	fedora	generic	37
nvd	haxx	libcurl	generic	≥ 7.69.0 and ＜ 8.4.0
nvd	microsoft	windows 10 1809	generic	＜ 10.0.17763.5122
nvd	microsoft	windows 10 21h2	generic	＜ 10.0.19044.3693
nvd	microsoft	windows 10 22h2	generic	＜ 10.0.19045.3693
nvd	microsoft	windows 11 21h2	generic	＜ 10.0.22000.2600
nvd	microsoft	windows 11 22h2	generic	＜ 10.0.22621.2715
nvd	microsoft	windows 11 23h2	generic	＜ 10.0.22631.2715
nvd	microsoft	windows server 2019	generic	＜ 10.0.17763.5122
nvd	microsoft	windows server 2022	generic	＜ 10.0.20348.2113
nvd	netapp	active iq unified manager	generic	any version
nvd	netapp	oncommand insight	generic	any version
nvd	netapp	oncommand workflow automation	generic	any version

Source

Vendor

Product

Scheme

Affected versions

nvd

fedoraproject

fedora

generic

nvd

haxx

libcurl

generic

≥ 7.69.0 and ＜ 8.4.0

nvd

microsoft

windows 10 1809

generic

＜ 10.0.17763.5122

nvd

microsoft

windows 10 21h2

generic

＜ 10.0.19044.3693

nvd

microsoft

windows 10 22h2

generic

＜ 10.0.19045.3693

nvd

microsoft

windows 11 21h2

generic

＜ 10.0.22000.2600

nvd

microsoft

windows 11 22h2

generic

＜ 10.0.22621.2715

nvd

microsoft

windows 11 23h2

generic

＜ 10.0.22631.2715

nvd

microsoft

windows server 2019

generic

＜ 10.0.17763.5122

nvd

microsoft

windows server 2022

generic

＜ 10.0.20348.2113

nvd

netapp

active iq unified manager

generic

any version

nvd

netapp

oncommand insight

generic

any version

nvd

netapp

oncommand workflow automation

generic

any version

References

URL	Tags
http://seclists.org/fulldisclosure/2024/Jan/34	Mailing List, Third Party Advisory
http://seclists.org/fulldisclosure/2024/Jan/37	Mailing List, Third Party Advisory
http://seclists.org/fulldisclosure/2024/Jan/38	Mailing List, Third Party Advisory
https://curl.se/docs/CVE-2023-38545.html	Patch, Third Party Advisory
https://forum.vmssoftware.com/viewtopic.php?f=8&t=8868
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/OGMXNRNSJ4ETDK6FRNU3J7SABXPWCHSQ/	Mailing List, Third Party Advisory
https://security.netapp.com/advisory/ntap-20231027-0009/	Third Party Advisory
https://security.netapp.com/advisory/ntap-20240201-0005/	Third Party Advisory
https://support.apple.com/kb/HT214036	Third Party Advisory
https://support.apple.com/kb/HT214057	Third Party Advisory

URL

Timeline

Published	2023-10-18	By the CVE Program.
NVD record modified	2026-06-17	NVD's own last-modified date for this record.

Published

2023-10-18

By the CVE Program.

NVD record modified

2026-06-17

NVD's own last-modified date for this record.

How VRT decided (5 of 24 rules ran)

5 of 24 rules ran. The rest didn't run because an earlier rule had already settled the CVE.

# Rule Outcome Status Detail

identity: Does this identifier describe a vulnerability at all? the first rule that matches decides

1 rejected no match CVE Program withdrawal of this identifier

scope: Is it a vulnerability Waratek protects? the first rule that matches decides

2 armr-patch-file no match An ARMR patch file on disk for this CVE

3 armr-secure-rule-file no match An ARMR security-rule template on disk for this CVE

4 manual-classification no match A researcher's recorded decision for this specific CVE

5 manual classification decided it matched Outside Waratek scope Found in legacy manual classifications

6 non-java-upstream not reached A root cause in non-Java code: an OS kernel, a C library, or a bundled runtime

7 oracle-component not reached The defect being in a component of a tracked product the agent does not reach: JavaFX, the Java SE installer, the JInitiator browser plug-in, the native WebLogic proxy plug-in, or a native part of Oracle Application Server or Collaboration Suite (HTTP Server, Web Cache, Internet Directory, mail and calendar servers). Oracle gives these no CPE of their own and names them only in the description.

8 java-client-side not reached Oracle's own risk-matrix note saying the CVE is reached only through untrusted code in the Java sandbox (applets, Web Start) or only through a client installation of Java, so a server running its own trusted code is not exposed

9 osv-maven not reached An OSV.dev record of this CVE affecting a package published to Maven Central. When every such package is one business applications do not use (Minecraft mods and launchers, Fastjson) and no tracked product is named by CPE, it settles the CVE as Outside Waratek scope instead

10 cna-maven-package not reached An affected Maven artifact named by the CNA itself

11 known-cpe-product not reached An NVD CPE naming a product ARMR tracks

12 cna-cpe-product not reached A CPE the CNA published naming a tracked product. Oracle publishes these on advisory day, months before NVD.

13 oracle-advisory-family not reached A tracked product family named in Oracle's own risk matrix. CPE cannot carry a suite name, only a module.

14 cna-named-product not reached A tracked product named in words by the CVE's own CNA, on a record with no CPE yet. Apache and Eclipse publish these on advisory day, before NVD adds CPE data.

15 non-deployable-product not reached The only affected product being a sealed appliance image, where Java runs but no -javaagent can be attached

16 unmatched-product not reached No tracked product matched above, and none present at all

disposition: What do we do about one that is? every rule runs

17 patch-hint not reached A reference pointing at the upstream fix: a commit, a PR, a Red Hat bug

18 open-source-maven not reached The affected package being open source on Maven, so the fix can be read

19 poc-derivable not reached An indexed exploit clearing the evidence bar to reverse-engineer, where there is no source to read

20 no-exploit not reached Nothing to build a rule from yet: no published exploit, no CISA record of exploitation and no source-level change to read

21 secure-rule-match not reached A vulnerability class already blocked by an ARMR security rule

22 exploited-no-fix-or-poc not reached Somebody exploiting this CVE (a CISA or VulnCheck KEV listing, or a CISA verdict of active exploitation), with no fix, source code or PoC to build a rule from

23 below-action-threshold not reached Medium or Low severity, no CISA or VulnCheck KEV listing, no PoC clearing the evidence bar, no CISA verdict, no Oracle advisory

24 no-exploit-published not reached Exploit code for this candidate, published in a reviewed catalogue or a GitHub repository with 5 or more stars, or in use per CISA or VulnCheck; not only a CISA verdict, a forecast, or nothing at all

NVD ↗ · CVE.org ↗