AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.0, attacker-controlled input included into multipart/payload headers can be used to modify a request to inject additional headers or similar. In the unlikely situation that an application is passing user-controlled strings into MultipartWriter.append(headers=...) or Payload.headers, then an attacker may be able to modify the request to inject headers or change the contents of the request. This vulnerability is fixed in 3.14.0.

The remote SUSE Linux SLES15 / SLES_SAP15 host has a package installed that is affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:3208-1 advisory.

    - CVE-2026-50269: improper validation of user-controlled strings allows for CRLF injection in multipart     headers       (bsc#1268398).
    - CVE-2026-54273: no limit in the HTTP/1 pipelined request queue can lead to excessive resource     consumption       (bsc#1268543).
    - CVE-2026-54274: incomplete websocket frame payloads can bypass memory use limits and cause a DoS via     excessive       resource consumption (bsc#1268544).
    - CVE-2026-54275: `server_hostname` TLS SNI check bypass when an existing connection is reused     (bsc#1268549).
    - CVE-2026-54277: `max_line_size` bypass when using the optimised C HTTP parser can lead to excessive     resource       consumption (bsc#1268556).
    - CVE-2026-54278: unread compressed request bodies can bypass `client_max_size` during cleanup and cause a     DoS       (bsc#1268559).
    - CVE-2026-54279: host-only cookies become domain cookies after `CookieJar` persistence (bsc#1268560).
    - CVE-2026-54280: payload resources are not closed correctly when a client disconnects in the middle of a     write and       can cause resource starvation (bsc#1268561).

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote SUSE Linux SLED15 / SLED_SAP15 / SLES15 / SLES_SAP15 host has a package installed that is affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:3207-1 advisory.

    This update for python-aiohttp fixes the following issues

    - CVE-2026-22815: insufficient restrictions in header/trailer handling can cause uncapped memory usage and     a denial of       service (bsc#1261320).
    - CVE-2026-34513: unbounded DNS cache can cause a excessive memory usage and lead to a denial of service     (bsc#1261321).
    - CVE-2026-34514: `content_type` parameter manipulation can lead to header injection (bsc#1261322).
    - CVE-2026-34516: response with excessive multipart headers can use more memory than intended and cause a     denial of       service (bsc#1261329).
    - CVE-2026-34517: large multipart form fields read into memory without size check can cause a denial of     service       (bsc#1261331).
    - CVE-2026-34518: retained `Cookie` and `Proxy-Authorization` headers when following redirects can lead to     information       disclosure (bsc#1261332).
    - CVE-2026-34519: response `reason` parameter can be use to perform header injection (bsc#1261334).
    - CVE-2026-34520: improper character handling by C parser can lead to header injection (bsc#1261335).
    - CVE-2026-34525: multiple `Host` headers allow for potential security bypass in proxy servers     (bsc#1261343).
    - CVE-2026-34993: loading untrusted input in `CookieJar.load()` can lead to arbitrary code execution     (bsc#1267471).
    - CVE-2026-47265: cookies set with the `cookies` parameter on requests are sent after following a cross-     origin redirect       and can leak sensitive data (bsc#1267561).
    - CVE-2026-50269: improper validation of user-controlled strings allows for CRLF injection in multipart     headers       (bsc#1268398).
    - CVE-2026-54273: no limit in the HTTP/1 pipelined request queue can lead to excessive resource     consumption       (bsc#1268543).
    - CVE-2026-54274: incomplete websocket frame payloads can bypass memory use limits and cause a DoS via     excessive       resource consumption (bsc#1268544).
    - CVE-2026-54275: `server_hostname` TLS SNI check bypass when an existing connection is reused     (bsc#1268549).
    - CVE-2026-54277: `max_line_size` bypass when using the optimised C HTTP parser can lead to excessive     resource       consumption (bsc#1268556).
    - CVE-2026-54278: unread compressed request bodies can bypass `client_max_size` during cleanup and cause a     DoS       (bsc#1268559).
    - CVE-2026-54279: host-only cookies become domain cookies after `CookieJar` persistence (bsc#1268560).
    - CVE-2026-54280: payload resources are not closed correctly when a client disconnects in the middle of a     write and       can cause resource starvation (bsc#1268561).

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote openSUSE 16 host has a package installed that is affected by multiple vulnerabilities as referenced in the openSUSE-SU-2026:21372-1 advisory.

    This update for python-aiohttp fixes the following issues

    - CVE-2026-50269: improper validation of user-controlled strings allows for CRLF injection in multipart     headers       (bsc#1268398).
    - CVE-2026-54273: no limit in the HTTP/1 pipelined request queue can lead to excessive resource     consumption       (bsc#1268543).
    - CVE-2026-54274: incomplete websocket frame payloads can bypass memory use limits and cause a DoS via     excessive       resource consumption (bsc#1268544).
    - CVE-2026-54275: `server_hostname` TLS SNI check bypass when an existing connection is reused     (bsc#1268549).
    - CVE-2026-54277: `max_line_size` bypass when using the optimised C HTTP parser can lead to excessive     resource       consumption (bsc#1268556).
    - CVE-2026-54278: unread compressed request bodies can bypass `client_max_size` during cleanup and cause a     DoS       (bsc#1268559).
    - CVE-2026-54279: host-only cookies become domain cookies after `CookieJar` persistence (bsc#1268560).
    - CVE-2026-54280: payload resources are not closed correctly when a client disconnects in the middle of a     write and       can cause resource starvation (bsc#1268561).

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The version of the aiohttp Python library installed on the remote host is prior to 3.14.0. It is, therefore, affected by a vulnerability:

  - Prior to 3.14.0, attacker-controlled input included into multipart/payload headers can be used to modify     a request to inject additional headers or similar. In the unlikely situation that an application is passing     user-controlled strings into MultipartWriter.append(headers=...) or Payload.headers, then an attacker may     be able to modify the request to inject headers or change the contents of the request. (CVE-2026-50269)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.0, attacker-     controlled input included into multipart/payload headers can be used to modify a request to inject     additional headers or similar. In the unlikely situation that an application is passing user-controlled     strings into MultipartWriter.append(headers=...) or Payload.headers, then an attacker may be able to     modify the request to inject headers or change the contents of the request. This vulnerability is fixed in     3.14.0. (CVE-2026-50269)

Note that Nessus relies on the presence of the package as reported by the vendor.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.0, attacker-
    controlled input included into multipart/payload headers can be used to modify a request to inject
    additional headers or similar. In the unlikely situation that an application is passing user-controlled
    strings into MultipartWriter.append(headers=...) or Payload.headers, then an attacker may be able to
    modify the request to inject headers or change the contents of the request. This vulnerability is fixed in
    3.14.0. (CVE-2026-50269)

ID	Name	Product	Family	Severity
329282	SUSE SLES15 Security Update : python-aiohttp (SUSE-SU-2026:3208-1)	Nessus	SuSE Local Security Checks	high
329280	SUSE SLED15 / SLES15 Security Update : python-aiohttp (SUSE-SU-2026:3207-1)	Nessus	SuSE Local Security Checks	high
328918	openSUSE 16 Security Update : python-aiohttp (openSUSE-SU-2026:21372-1)	Nessus	SuSE Local Security Checks	high
324957	Python Library aiohttp < 3.14.0 Header Injection	Nessus	Misc.	medium
322127	Linux Distros Unpatched Vulnerability : CVE-2026-50269	Nessus	Misc.	medium
443263	SCA: security update for aiohttp (GHSA-m6qw-4cw2-hm4m)	Tenable Cloud Security	SCA Checks	medium
443263	SCA: security update for aiohttp (GHSA-m6qw-4cw2-hm4m)	Tenable Self-Hosted Container Security	SCA Checks	medium

Detections

Analytics

CVE-2026-50269

medium

Tenable Plugins

high

high

high

medium

medium

medium

medium