{"id":"CVE-2026-54278","aliases":["GHSA-g3cq-j2xw-wf74","PYSEC-2026-2111"],"url":"https://o3.security/vulnerability/CVE-2026-54278","summary":"AIOHTTP: Unread Compressed Request Bodies Bypass client_max_size During Cleanup","details":"AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.1, during cleanup it is possible for a compressed request body to be decompressed into memory in one chunk. An attacker may be able to send a compressed payload in specific situations that could be decompressed into memory, potentially leading to DoS (a zip bomb edge case). This vulnerability is fixed in 3.14.1.","published":"2026-06-22T16:38:38.838Z","modified":"2026-08-12T03:51:45.619954875Z","cvss":null,"epss":{"score":0.00397,"percentile":0.33504,"asOf":"2026-09-16"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"PyPI","name":"aiohttp","fixedVersion":"3.14.1"}],"fix":{"url":"https://github.com/aio-libs/aiohttp/commit/4f7480e474cccc6a8cc2c92ad3f17a31dedf8232","label":"aio-libs/aiohttp@4f7480e"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54278.json"},{"type":"ADVISORY","url":"https://github.com/aio-libs/aiohttp/security/advisories/GHSA-g3cq-j2xw-wf74"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-54278"},{"type":"FIX","url":"https://github.com/aio-libs/aiohttp/commit/4f7480e474cccc6a8cc2c92ad3f17a31dedf8232"},{"type":"PACKAGE","url":"https://github.com/aio-libs/aiohttp"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:45.619954875Z"}}