Answer in brief
CVE-2026-54278 records a High severity (CVSS 7.5) vulnerability in aiohttp: Unread Compressed Request Bodies Bypass client_max_size During Cleanup. The current sources do not mark it as known exploited. The current feed maps aiohttp (pip), aiohttp (pypi). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps aiohttp (pip), aiohttp (pypi). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| aiohttppip | <=3.14.0 | 3.14.1 |
| aiohttppypi | >=0 <3.14.1 | 3.14.1 |
Published upstream
Jun 15, 2026
Evidence: source:osv:source_dates:source-dates:recordSource modified
Sep 10, 2026
Evidence: source:osv:source_dates:source-dates:recordFirst seen by HOL
Jun 19, 2026
### Summary During cleanup it is possible for a compressed request body to be decompressed into memory in one chunk. ### Impact 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). ### Workaround Disable compression if unable to upgrade. ----- Patch: https://github.com/aio-libs/aiohttp/commit/4f7480e474cccc6a8cc2c92ad3f17a31dedf8232
Quoted source text, attributed separately from HOL analysis.