How severe is CVE-2025-54574?

CVE-2025-54574 has a CVSS 3.x base score of 9.3, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability high.

Is CVE-2025-54574 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 23% (97th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-54574?

CVE-2025-54574 affects Squid-cache Squid. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-54574?

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.

Does CVE-2025-54574 have an EU (EUVD) identifier?

Yes. CVE-2025-54574 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-23392.

When was CVE-2025-54574 published?

CVE-2025-54574 was published on 2025-08-01 and last updated on 2026-06-17.

CVE-2025-54574

CVE-2025-54574 is a critical-severity vulnerability in Squid-cache Squid with a CVSS 3.x base score of 9.3. Its EPSS exploit-prediction score of 23% places it in the 97th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-787.

Key facts

Severity: Critical (CVSS 3.x base score 9.3)
EPSS exploit prediction: 23% (97th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-23392
Weakness: CWE-787
Affected product: Squid-cache Squid
Published: 2025-08-01
Last modified: 2026-06-17

Description

Squid is a caching proxy for the Web. In versions 6.3 and below, Squid is vulnerable to a heap buffer overflow and possible remote code execution attack when processing URN due to incorrect buffer management. This has been fixed in version 6.4. To work around this issue, disable URN access permissions.

Frequently asked questions

What is CVE-2025-54574?: Squid is a caching proxy for the Web. In versions 6.3 and below, Squid is vulnerable to a heap buffer overflow and possible remote code execution attack when processing URN due to incorrect buffer management. This has been fixed in version 6.4. To work around this issue, disable URN access permissions.
How severe is CVE-2025-54574?: CVE-2025-54574 has a CVSS 3.x base score of 9.3, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability high.
Is CVE-2025-54574 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 23% (97th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-54574?: CVE-2025-54574 affects Squid-cache Squid. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-54574?: 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.
Does CVE-2025-54574 have an EU (EUVD) identifier?: Yes. CVE-2025-54574 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-23392.
When was CVE-2025-54574 published?: CVE-2025-54574 was published on 2025-08-01 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*

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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:

78.39.48.166 (ipv4-addr)
212.58.132.5 (ipv4-addr)
103.200.23.154 (ipv4-addr)
200.89.159.59 (ipv4-addr)
103.54.101.248 (ipv4-addr)
74.113.233.217 (ipv4-addr)
192.3.127.40 (ipv4-addr)