{"id":"CVE-2026-54278","aliases":["GHSA-g3cq-j2xw-wf74","PYSEC-2026-2111"],"title":"aiohttp: Unread Compressed Request Bodies Bypass client_max_size During Cleanup","summary":"aiohttp: Unread Compressed Request Bodies Bypass client_max_size During Cleanup","severity":"medium","vendor":"aiohttp","product":"aiohttp","ecosystem":"pip","affected":["aiohttp < 3.14.1"],"patched":["aiohttp 3.14.1"],"published":"2026-06-15","updated":"2026-09-10","sourceUpdated":"2026-09-10T03:51:08.751749295Z","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GHSA-g3cq-j2xw-wf74","references":[{"url":"https://github.com/aio-libs/aiohttp/security/advisories/GHSA-g3cq-j2xw-wf74"},{"url":"https://github.com/aio-libs/aiohttp"},{"url":"https://github.com/advisories/GHSA-g3cq-j2xw-wf74"}],"tags":["osv","pip","ghsa"],"epss":0.00397,"epssPercentile":0.33756,"cwe":["CWE-409"],"ingestedAt":"2026-07-07T15:41:58.688Z","slug":"CVE-2026-54278","body":"## Overview\n\n### Summary\n\nDuring cleanup it is possible for a compressed request body to be decompressed into memory in one chunk.\n\n### Impact\n\nAn 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).\n\n### Workaround\n\nDisable compression if unable to upgrade.\n\n-----\n\nPatch: https://github.com/aio-libs/aiohttp/commit/4f7480e474cccc6a8cc2c92ad3f17a31dedf8232\n\n## Affected packages\n\n- `aiohttp < 3.14.1`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `aiohttp 3.14.1`","depth":"sunlit","depthScore":28,"depthScoreParts":{"impact":27.5,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}