CVE-2026-121006

HIGH
Published Nov 6, 2026 Modified Nov 12, 2026 CWE-770

Description

HTTP::Body versions before 1.24_02 for Perl parse the trailer in quadratic time. Everything after the last chunk in the same call to add() is parsed with HTTP::Headers, which takes time quadratic in the number of fields of one name. For example, it takes several seconds to parse 16 KiB of "a:" lines. A remote attackercan exhause the CPU with a single request. HTTP::Body version 1.25 limits the size and number of lines in the trailer.

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CVSS v3.1 Score

7.5
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS — Exploit Prediction

0.0042
Probability of exploitation
0.37%
Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-770 CWE-770

References

Frequently Asked Questions

What is CVE-2026-121006? +
HTTP::Body versions before 1.24_02 for Perl parse the trailer in quadratic time. Everything after the last chunk in the same call to add() is parsed with HTTP::Headers, which takes time quadratic in the number of fields of one name. For example, it takes several seconds to parse 16 KiB of "a:" lines. A remote attackercan exhause the CPU with a single request. HTTP::Body version 1.25 limits the size and number of lines in the trailer. It has a CVSS v3.1 base score of 7.5 (HIGH).
How severe is CVE-2026-121006? +
CVE-2026-121006 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0042, placing it in the 0th percentile for exploitation probability.
How do I check if I'm vulnerable to CVE-2026-121006? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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