CVE-2024-30251
highpriority · track · 0EPSS 0.011 · 65 %ileDEEUNLRUUSEPSS · scored 2026-10-27
aiohttp is an asynchronous HTTP client/server framework for asyncio and Python. In affected versions an attacker can send a specially crafted POST (multipart/form-data) request. When the aiohttp server processes it, the server will enter an infinite loop and be unable to process any further requests. An attacker can stop the application from serving requests after sending a single request. This issue has been addressed in version 3.9.4. Users are advised to upgrade. Users unable to upgrade may manually apply a patch to their systems. Please see the linked GHSA for instructions.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–7.5
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (61)
Products and version ranges known to be affected.
- Red Hat Enterprise Linux Update Infrastructure 4all versionscert_bundDEcpe:/o:redhat:enterprise_linux:update_infrastructure_4
advisories (5)
Vendor and ecosystem advisories describing this.
- NCSC-2024-0414Kwetsbaarheden verholpen in Oracle CommunicationsNL2024-10-17csaf · ncsc_nlNL
Oracle heeft kwetsbaarheden verholpen in diverse Communications producten en systemen.
- WID-SEC-W-2024-1328Red Hat Ansible Automation Platform: Mehrere SchwachstellenDeutsch2024-06-10csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Red Hat Ansible Automation Platform ausnutzen, um beliebigen Programmcode auszuführen, einen Denial-of-Service-Zustand erzeugen, vertrauliche Informationen offenzulegen, Sicherheitsmaßnahmen zu umgehen, Dateien zu manipulieren oder Cross-Site-Scripting (XSS)-Angriffe durchzuführen.
- WID-SEC-W-2024-3195Oracle Communications: Mehrere SchwachstellenDeutsch2024-10-15csaf · cert_bundDE
Ein entfernter, anonymer oder authentisierter Angreifer kann mehrere Schwachstellen in Oracle Communications ausnutzen, um die Vertraulichkeit, Integrität und Verfügbarkeit zu gefährden.
- GHSA-5m98-qgg9-wh84aiohttp vulnerable to Denial of Service when trying to parse malformed POST requests2024-05-03ghsa · osvUS
### Summary An attacker can send a specially crafted POST (multipart/form-data) request. When the aiohttp server processes it, the server will enter an infinite loop and be unable to process any further requests. ### Impact An attacker can stop the application from serving requests after sending a single request. ------- For anyone needing to patch older versions of aiohttp, the minimum diff needed to resolve the issue is (located in `_read_chunk_from_length()`): ```diff diff --git a/aiohttp/multipart.py b/aiohttp/multipart.py index 227be605c..71fc2654a 100644 --- a/aiohttp/multipart.py +++ b/aiohttp/multipart.py @@ -338,6 +338,8 @@ class BodyPartReader: assert self._length is not None, "Content-Length required for chunked read" chunk_size = min(size, self._length - self._read_bytes) chunk = await self._content.read(chunk_size) + if self._content.at_eof(): + self._at_eof = True return chunk async def _read_chunk_from_stream(self, size: int) -> bytes: ``` This does however introduce some very minor issues with handling form data. So, if possible, it would be recommended to also backport the changes in: https://github.com/aio-libs/aiohttp/commit/cebe526b9c34dc3a3da9140409db63014bc4cf19 https://github.com/aio-libs/aiohttp/commit/7eecdff163ccf029fbb1ddc9de4169d4aaeb6597 https://github.com/aio-libs/aiohttp/commit/f21c6f2ca512a026ce7f0f6c6311f62d6a638866
- PYSEC-2026-1098aiohttp vulnerable to Denial of Service when trying to parse malformed POST requests2026-07-07vendor · osvUS
### Summary An attacker can send a specially crafted POST (multipart/form-data) request. When the aiohttp server processes it, the server will enter an infinite loop and be unable to process any further requests. ### Impact An attacker can stop the application from serving requests after sending a single request. ------- For anyone needing to patch older versions of aiohttp, the minimum diff needed to resolve the issue is (located in `_read_chunk_from_length()`): ```diff diff --git a/aiohttp/multipart.py b/aiohttp/multipart.py index 227be605c..71fc2654a 100644 --- a/aiohttp/multipart.py +++ b/aiohttp/multipart.py @@ -338,6 +338,8 @@ class BodyPartReader: assert self._length is not None, "Content-Length required for chunked read" chunk_size = min(size, self._length - self._read_bytes) chunk = await self._content.read(chunk_size) + if self._content.at_eof(): + self._at_eof = True return chunk async def _read_chunk_from_stream(self, size: int) -> bytes: ``` This does however introduce some very minor issues with handling form data. So, if possible, it would be recommended to also backport the changes in: https://github.com/aio-libs/aiohttp/commit/cebe526b9c34dc3a3da9140409db63014bc4cf19 https://github.com/aio-libs/aiohttp/commit/7eecdff163ccf029fbb1ddc9de4169d4aaeb6597 https://github.com/aio-libs/aiohttp/commit/f21c6f2ca512a026ce7f0f6c6311f62d6a638866
also known as (7)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (18)
External citations — patches, advisories, analysis.
- http://www.openwall.com/lists/oss-security/2024/05/02/4cnnvd
- https://access.redhat.com/security/cve/cve-2024-30251cnnvd
- https://cxsecurity.com/cveshow/CVE-2024-30251/cnnvd
- https://github.com/aio-libs/aiocnnvd
- https://github.com/aio-libs/aiohttp/releases/tag/v3.9.5Patchcnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2024-30251cnnvd
- https://www.oracle.com/security-alerts/cpuoct2024.htmlcnnvd
- http://www.openwall.com/lists/oss-security/2024/05/02/4enisa_euvd
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