Unauthenticated service interruption via unbounded chunk-size parsing
Published May 11, 2026 · Updated May 11, 2026
Uncontrolled resource consumption in Nine Nines Cowlib 0.6.0 through 2.16.0 allows remote attackers to interrupt service via HTTP/1.1. The cow_http_te:chunked_len/4 parser repeatedly multiplies an unbounded chunk-size hex value into a growing Erlang bignum, while partial reads restart the calculation. No authentication is required, and exploitation exhausts CPU and memory in a network-facing application that passes chunked bodies to the parser.
Summary
What happened
Uncontrolled resource consumption in Nine Nines Cowlib 0.6.0 through 2.16.0 allows remote attackers to interrupt service via HTTP/1.1. The cow_http_te:chunked_len/4 parser repeatedly multiplies an unbounded chunk-size hex value into a growing Erlang bignum, while partial reads restart the calculation. No authentication is required, and exploitation exhausts CPU and memory in a network-facing application that passes chunked bodies to the parser.
The record
- CVE
- CVE-2026-7790
- Published
- May 11, 2026
- Updated
- May 11, 2026
- Vendor
- Nine Nines
- Product
- Cowlib
- Classifications
- CWE-400, CAPEC-130, T1499.003
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 11, 2026CVE publishedPublication date reported by the CVE source.
- May 11, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0.6.0 <2.16.1
- Affected versionversion=8c0e428b012c59f553a264f285ed89d36f791e3e <a4b8039ce8c93ab00867ef6b7e888822c09f4369
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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