How severe is CVE-2026-17544?

CVE-2026-17544 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-17544 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-17544?

CVE-2026-17544 affects Php. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-17544?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2026-17544 published?

CVE-2026-17544 was published on 2026-07-30 and last updated on 2026-08-05.

CVE-2026-17544

CVE-2026-17544 is a critical-severity vulnerability in Php with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v4: 8.1
EPSS exploit prediction: 1% (42nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Php
Published: 2026-07-30
Last modified: 2026-08-05

Description

Attacker-provided inputs to bccomp() could lead to an out-of-bounds write with stack and heap corruption in PHP versions from 8.4.* before 8.4.24 and from 8.5.* before 8.5.9.

Frequently asked questions

What is CVE-2026-17544?: Attacker-provided inputs to bccomp() could lead to an out-of-bounds write with stack and heap corruption in PHP versions from 8.4.* before 8.4.24 and from 8.5.* before 8.5.9.
How severe is CVE-2026-17544?: CVE-2026-17544 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-17544 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-17544?: CVE-2026-17544 affects Php. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-17544?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2026-17544 published?: CVE-2026-17544 was published on 2026-07-30 and last updated on 2026-08-05.

References

https://github.com/php/php-src/security/advisories/GHSA-x692-q9x7-8c3f

Affected products (1)

cpe:2.3:a:php:php:*:*:*:*:*:*:*:*

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CVE-2024-42479 — Critical (CVSS 10.0): llama.cpp provides LLM inference in C/C++. The unsafe `data` pointer member in the `rpc_tensor` structure can cause…
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Browse all CWE-787 (Out-of-bounds Write) vulnerabilities →

Threat intelligence

Threat-intel indicators referencing this CVE:

31.216.62.126 (ipv4-addr)
185.7.172.105 (ipv4-addr)
112.155.126.105 (ipv4-addr)
185.97.117.108 (ipv4-addr)
143.244.172.83 (ipv4-addr)
107.174.184.189 (ipv4-addr)
222.221.107.229 (ipv4-addr)
185.201.132.19 (ipv4-addr)