cvedb.io
CVE-2026-7790
HIGH · CVSS 7.5
EPSS exploitation probability: 0%
Published 2026-05-11T19:16:29.477 · Last modified 2026-06-17T11:02:58.127

Summary

Uncontrolled Resource Consumption vulnerability in ninenines cowlib (cow_http_te module) allows Excessive Allocation. The chunked transfer-encoding parser in cow_http_te accepts an unbounded number of hex digits in the chunk-size field. Each digit causes a bignum multiplication (Len * 16 + digit), so parsing N hex digits requires O(N²) CPU work and O(N) memory. Additionally, when input is drip-fed, the parser discards the accumulated length on each partial read and restarts from zero on resumption, raising the cost to O(N³). An unauthenticated remote attacker can exploit this by sending an HTTP/1.1 request with Transfer-Encoding: chunked and a very long chunk-size hex string to cause denial of service through CPU exhaustion and memory amplification. This vulnerability is associated with

Affected products

ninenines — cowlib

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.