CVE-2026-128128: aio-libs aiohttp · Unthrottled Resource Allocation
Affects aio-libs aiohttpSource CVE Database V5
Not known to be exploited · CVSS 7.5 High : upgrade to 3.14.4 soon.
Data as of 13 Nov 2026, 20:48 UTC
Thin evidence
One scorer or none| CNA (GitHub_M) | CVSS 3.1 | 7.5 |
|---|
- Patch
- Available – fixed in 3.14.4
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 13 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 13 Nov 2026.
What to do
Upgrade aio-libs aiohttp to 3.14.4.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| aio-libsaiohttp | Affected
| Fixed in
|
AI-suggested
Upgrade aiohttp to version 3.14.4 or later, where this vulnerability is fixed. No other mitigation is required as the fix addresses the root cause.
Description
CVE-2026-128128 is a vulnerability in aiohttp versions prior to 3.14.4 where the C WebSocket reader uses signed 64-bit arithmetic to add a declared frame length to an already buffered partial message size. This can cause an integer overflow near 2^63, bypassing the max_msg_size check and allowing a remote attacker to cause unbounded memory consumption by sending a small non-final fragment followed by an oversized message. The Python WebSocket reader is not affected. The issue is fixed in version 3.14.4.
References
- github.com/aio-libs/aiohttp/security/advisories/GHSA-3rp8-rxj8-mvjw (opens in a new tab)
- github.com/aio-libs/aiohttp/pull/13415 (opens in a new tab)
- github.com/aio-libs/aiohttp/pull/13494 (opens in a new tab)
- github.com/aio-libs/aiohttp/commit/8c8906a19f64e52ef6a7d44d65217eb3c5af413f (opens in a new tab)
- github.com/aio-libs/aiohttp/commit/8cfbe9abe5e11b84006a10f9bdf82bf607671dab (opens in a new tab)
- github.com/aio-libs/aiohttp/releases/tag/v3.14.4 (opens in a new tab)