Medium Http4s CVEs

7 CVEs, 2 protected by Waratek

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Overview 7 matches · 2 protected · 0 exploited · 0 CISA KEV · 0 public PoC · 0 EPSS ≥ 0.5

7matches 2protected28.6% 0exploited0.0% 0CISA KEV0.0% 0public PoC0.0% 0EPSS ≥ 0.50.0%

Protected by Waratek 2 28.6% Rule in development 0 0.0% Mitigation candidate 0 0.0% No exploit published 5 71.4%

Critical 0 0.0% High 0 0.0% Medium 7 100.0% Low 0 0.0% None 0 0.0% Unknown 0 0.0%

blocked by ARMR today 2 28.6% partly blocked 0 0.0% not blocked 5 71.4% not established 0 0.0% unrecorded 0 0.0%

Exploited 0 0.0% Working exploit published 0 0.0% Proof of concept only 1 14.3% Forecast only 0 0.0% No public exploit 6 85.7%

split by StatusSeverityProtectionExploit maturity peak 5 / quarter

Q2 211 Protected by Waratek1 Medium1 blocked by ARMR today1 No public exploit1 Q3 210 Q4 210 Q1 220 Q2 220 Q3 220 Q4 220 Q1 230 Q2 230 Q3 230 Q4 230 Q1 240 Q2 240 Q3 240 Q4 240 Q1 250 Q2 250 Q3 251 No exploit published1 Medium1 not blocked1 Proof of concept only1 Q4 250 Q1 260 Q2 260 Q3 265 Protected by Waratek1 No exploit published4 Medium5 blocked by ARMR today1 not blocked4 No public exploit5

Q3 21Q1 22Q3 22Q1 23Q3 23Q1 24Q3 24Q1 25Q3 25Q1 26Q3 26

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CVE	Severity	Published▾	Status	Exploitation	Description
CVE-2026-69216	Medium	2026-09-15	No exploit published	No public exploit	Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, Ember’s chunk decoder trims the chunk-size token and accepts leading plus or minus signs instead of requiring one or more hexadecimal digits followed by the required CRLF. When an intermediary forwards chunked data without re-encoding and interprets malformed chunk boundaries differently, an unauthenticated attacker can create TE.TE request smuggling that bypasses intermediary controls, poisons caches, or hijacks the request queue. The same response-path leniency can enable response smuggling against an ember-client used as a gateway when the upstream is malicious or compromised. This issue is fixed in versions 0.23.35 and 1.0.0-M47.
CVE-2026-69215	Medium	2026-09-15	No exploit published	No public exploit	Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, The CookieJar client middleware uses unanchored substring checks instead of RFC 6265 domain and path matching when deciding whether to attach a stored cookie. A cookie for example.com can consequently be sent to an attacker-controlled hostname such as evilexample.com when an application using the same jar makes an attacker-influenced outbound request. This exposes session or authentication cookies and can enable hijacking of the application’s outbound sessions. This issue is fixed in versions 0.23.35 and 1.0.0-M47.
CVE-2026-69214	Medium	2026-09-15	No exploit published	No public exploit	Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, The CookieJar client middleware stores a response cookie’s Domain attribute without checking that it domain-matches the host that supplied the cookie or rejecting public suffixes. A malicious or compromised server contacted through the same CookieJar can plant a cookie for another domain, and the jar later sends that cookie to the victim domain, enabling session fixation or overwriting security-sensitive cookies. The patch validates the Set-Cookie domain against the response origin, although public-suffix rejection remains unimplemented. This issue is fixed in versions 0.23.35 and 1.0.0-M47.
CVE-2026-69206	Medium	2026-09-15	No exploit published	No public exploit	Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, DigestAuth replay protection records lastNc plus one instead of the highest nonce-count value it has accepted. When a legitimate client sends noncontiguous nc values because of parallel or retried requests, the stored counter remains below the accepted maximum, allowing a passive observer to replay a captured Authorization header multiple times. Successful replays execute authenticated requests, including state-changing operations, as the captured user. This issue is fixed in versions 0.23.35 and 1.0.0-M47.
CVE-2026-69201	Medium	2026-09-15	Protected by Waratek	No public exploit	Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, ResourceService and WebjarService decode each URL path segment but reject only segments exactly equal to an empty string, a dot, or two dots. A request containing percent-encoded slash or backslash separators can turn an accepted segment into a parent-directory traversal after decoding, allowing access to classpath or WebJar resources outside the configured base when a directory-backed classpath is served and the backend preserves the encoded separator. The patch rejects decoded segments containing slash or backslash in ResourceService and WebjarService, and applies the same guard to the non-exploitable FileService for consistency. This issue is fixed in versions 0.23.35 and 1.0.0-M47.
CVE-2025-59822	Medium	2025-09-23	No exploit published	Proof of concept only	Http4s is a Scala interface for HTTP services. In versions from 1.0.0-M1 to before 1.0.0-M45 and before 0.23.31, http4s is vulnerable to HTTP Request Smuggling due to improper handling of HTTP trailer section. This vulnerability could enable attackers to bypass front-end servers security controls, launch targeted attacks against active users, and poison web caches. A pre-requisite for exploitation involves the web application being deployed behind a reverse-proxy that forwards trailer headers. This issue has been patched in versions 1.0.0-M45 and 0.23.31.
CVE-2021-32643	Medium	2021-05-27	Protected by Waratek	No public exploit	Http4s is a Scala interface for HTTP services. `StaticFile.fromUrl` can leak the presence of a directory on a server when the `URL` scheme is not `file://`, and the URL points to a fetchable resource under its scheme and authority. The function returns `F[None]`, indicating no resource, if `url.getFile` is a directory, without first checking the scheme or authority of the URL. If a URL connection to the scheme and URL would return a stream, and the path in the URL exists as a directory on the server, the presence of the directory on the server could be inferred from the 404 response. The contents and other metadata about the directory are not exposed. This affects http4s versions: 0.21.7 through 0.21.23, 0.22.0-M1 through 0.22.0-M8, 0.23.0-M1, and 1.0.0-M1 through 1.0.0-M22. The [patch](https://github.com/http4s/http4s/commit/52e1890665410b4385e37b96bc49c5e3c708e4e9) is available in the following versions: v0.21.24, v0.22.0-M9, v0.23.0-M2, v1.0.0-M23. As a workaround users can avoid calling `StaticFile.fromUrl` with non-file URLs.

CVE

Severity

Published▾

Status

Exploitation

Description

CVE-2026-69216

Medium

2026-09-15

No exploit published

No public exploit

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, Ember’s chunk decoder trims the chunk-size token and accepts leading plus or minus signs instead of requiring one or more hexadecimal digits followed by the required CRLF. When an intermediary forwards chunked data without re-encoding and interprets malformed chunk boundaries differently, an unauthenticated attacker can create TE.TE request smuggling that bypasses intermediary controls, poisons caches, or hijacks the request queue. The same response-path leniency can enable response smuggling against an ember-client used as a gateway when the upstream is malicious or compromised. This issue is fixed in versions 0.23.35 and 1.0.0-M47.

CVE-2026-69215

Medium

2026-09-15

No exploit published

No public exploit

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, The CookieJar client middleware uses unanchored substring checks instead of RFC 6265 domain and path matching when deciding whether to attach a stored cookie. A cookie for example.com can consequently be sent to an attacker-controlled hostname such as evilexample.com when an application using the same jar makes an attacker-influenced outbound request. This exposes session or authentication cookies and can enable hijacking of the application’s outbound sessions. This issue is fixed in versions 0.23.35 and 1.0.0-M47.

CVE-2026-69214

Medium

2026-09-15

No exploit published

No public exploit

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, The CookieJar client middleware stores a response cookie’s Domain attribute without checking that it domain-matches the host that supplied the cookie or rejecting public suffixes. A malicious or compromised server contacted through the same CookieJar can plant a cookie for another domain, and the jar later sends that cookie to the victim domain, enabling session fixation or overwriting security-sensitive cookies. The patch validates the Set-Cookie domain against the response origin, although public-suffix rejection remains unimplemented. This issue is fixed in versions 0.23.35 and 1.0.0-M47.

CVE-2026-69206

Medium

2026-09-15

No exploit published

No public exploit

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, DigestAuth replay protection records lastNc plus one instead of the highest nonce-count value it has accepted. When a legitimate client sends noncontiguous nc values because of parallel or retried requests, the stored counter remains below the accepted maximum, allowing a passive observer to replay a captured Authorization header multiple times. Successful replays execute authenticated requests, including state-changing operations, as the captured user. This issue is fixed in versions 0.23.35 and 1.0.0-M47.

CVE-2026-69201

Medium

2026-09-15

Protected by Waratek

No public exploit

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, ResourceService and WebjarService decode each URL path segment but reject only segments exactly equal to an empty string, a dot, or two dots. A request containing percent-encoded slash or backslash separators can turn an accepted segment into a parent-directory traversal after decoding, allowing access to classpath or WebJar resources outside the configured base when a directory-backed classpath is served and the backend preserves the encoded separator. The patch rejects decoded segments containing slash or backslash in ResourceService and WebjarService, and applies the same guard to the non-exploitable FileService for consistency. This issue is fixed in versions 0.23.35 and 1.0.0-M47.

CVE-2025-59822

Medium

2025-09-23

No exploit published

Proof of concept only

Http4s is a Scala interface for HTTP services. In versions from 1.0.0-M1 to before 1.0.0-M45 and before 0.23.31, http4s is vulnerable to HTTP Request Smuggling due to improper handling of HTTP trailer section. This vulnerability could enable attackers to bypass front-end servers security controls, launch targeted attacks against active users, and poison web caches. A pre-requisite for exploitation involves the web application being deployed behind a reverse-proxy that forwards trailer headers. This issue has been patched in versions 1.0.0-M45 and 0.23.31.

CVE-2021-32643

Medium

2021-05-27

Protected by Waratek

No public exploit

Http4s is a Scala interface for HTTP services. `StaticFile.fromUrl` can leak the presence of a directory on a server when the `URL` scheme is not `file://`, and the URL points to a fetchable resource under its scheme and authority. The function returns `F[None]`, indicating no resource, if `url.getFile` is a directory, without first checking the scheme or authority of the URL. If a URL connection to the scheme and URL would return a stream, and the path in the URL exists as a directory on the server, the presence of the directory on the server could be inferred from the 404 response. The contents and other metadata about the directory are not exposed. This affects http4s versions: 0.21.7 through 0.21.23, 0.22.0-M1 through 0.22.0-M8, 0.23.0-M1, and 1.0.0-M1 through 1.0.0-M22. The [patch](https://github.com/http4s/http4s/commit/52e1890665410b4385e37b96bc49c5e3c708e4e9) is available in the following versions: v0.21.24, v0.22.0-M9, v0.23.0-M2, v1.0.0-M23. As a workaround users can avoid calling `StaticFile.fromUrl` with non-file URLs.