CVE-2026-7259

LOWCVSS 2.1/10EPSS 0.20%

Last modified

CVE-2026-7259 is a low-severity vulnerability rated 2.1/10 on the CVSS scale. In PHP versions 8.2.* before 8.2.31, 8.3.* before 8.3.31, 8.4.* before 8.4.21, and 8.5.* before 8.5.6, a mismatch between encoding lists in Oniguruma and mbfl leads to  a NULL pointer dereference, resulting in a segmentation fault and denial of service. The vulnerability is exploitable when user-controlled input can influence the encoding passed to mb_regex_encoding().. EPSS estimates a 0.20% chance of exploitation in the next 30 days.

Description

In PHP versions 8.2.* before 8.2.31, 8.3.* before 8.3.31, 8.4.* before 8.4.21, and 8.5.* before 8.5.6, a mismatch between encoding lists in Oniguruma and mbfl leads to  a NULL pointer dereference, resulting in a segmentation fault and denial of service. The vulnerability is exploitable when user-controlled input can influence the encoding passed to mb_regex_encoding().

Metrics

CVSS 3.1
6.5/10

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

CVSS 4.0
2.1/10

CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:X/V:X/RE:X/U:Amber

EPSS Probability
0.20%

10.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

VendorProductVersions
PhpPhp>= 8.2.0, < 8.2.31
PhpPhp>= 8.3.0, < 8.3.31
PhpPhp>= 8.4.0, < 8.4.21
PhpPhp>= 8.5.0, < 8.5.6

References

Timeline

Published
Last Modified
Status
Analyzed

Frequently Asked Questions

What is CVE-2026-7259?
In PHP versions 8.2.* before 8.2.31, 8.3.* before 8.3.31, 8.4.* before 8.4.21, and 8.5.* before 8.5.6, a mismatch between encoding lists in Oniguruma and mbfl leads to  a NULL pointer dereference, resulting in a segmentation fault and denial of service. The vulnerability is exploitable when user-controlled input can influence the encoding passed to mb_regex_encoding().
How severe is CVE-2026-7259?
CVE-2026-7259 has a CVSS score of 2.1/10 (LOW severity). The EPSS model estimates a 0.20% probability of exploitation in the next 30 days.
How do I fix CVE-2026-7259?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-7259?

Run a free Strix scan to check your systems for this vulnerability.

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Source: NVD / NIST