How severe is CVE-2026-50012?

CVE-2026-50012 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability high.

Is CVE-2026-50012 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-50012?

CVE-2026-50012 affects Squid-cache Squid. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-50012?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2026-50012 published?

CVE-2026-50012 was published on 2026-07-16 and last updated on 2026-07-20.

CVE-2026-50012

CVE-2026-50012 is a medium-severity vulnerability in Squid-cache Squid with a CVSS 3.x base score of 5.5. 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-20.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 1% (70th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Squid-cache Squid
Published: 2026-07-16
Last modified: 2026-07-20

Description

Squid is a caching proxy for the Web. Prior to 7.6, due to an improper input validation bug in cache digest reply handling (peerDigestSwapInMask in src/peer_digest.cc), Squid is vulnerable to a heap-based buffer overflow: a cache digest's on-the-wire size may be larger than the mask_size declared within the digest, so a trusted peer sending a maliciously crafted reply to a cache_digest request message can trigger the overflow. This attack is limited to Squid instances compiled with the --enable-cache-digests option and configured with cache_peer entries. This issue is fixed in version 7.6.

Frequently asked questions

What is CVE-2026-50012?: Squid is a caching proxy for the Web. Prior to 7.6, due to an improper input validation bug in cache digest reply handling (peerDigestSwapInMask in src/peer_digest.cc), Squid is vulnerable to a heap-based buffer overflow: a cache digest's on-the-wire size may be larger than the mask_size declared within the digest, so a trusted peer sending a maliciously crafted reply to a cache_digest request message can trigger the overflow. This attack is limited to Squid instances compiled with the --enable-cache-digests option and configured with cache_peer entries. This issue is fixed in version 7.6.
How severe is CVE-2026-50012?: CVE-2026-50012 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability high.
Is CVE-2026-50012 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-50012?: CVE-2026-50012 affects Squid-cache Squid. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-50012?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-50012 published?: CVE-2026-50012 was published on 2026-07-16 and last updated on 2026-07-20.

References

Affected products (1)

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

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Other CWE-20 (Improper Input Validation) vulnerabilities

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CVE-2026-48316 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
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Threat intelligence

Threat-intel indicators referencing this CVE:

159.89.207.161 (ipv4-addr)
107.189.8.16 (ipv4-addr)
23.94.28.177 (ipv4-addr)
39.100.82.100 (ipv4-addr)
201.48.108.11 (ipv4-addr)
103.240.214.2 (ipv4-addr)
82.115.17.167 (ipv4-addr)
64.188.119.33 (ipv4-addr)