How severe is CVE-2023-49286?

CVE-2023-49286 has a CVSS 3.x base score of 8.6, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2023-49286 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 10% (95th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-49286?

CVE-2023-49286 affects Squid-cache Squid. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-49286?

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

When was CVE-2023-49286 published?

CVE-2023-49286 was published on 2023-12-04 and last updated on 2026-06-17.

CVE-2023-49286

CVE-2023-49286 is a high-severity vulnerability in Squid-cache Squid with a CVSS 3.x base score of 8.6. Its EPSS exploit-prediction score of 10% places it in the 95th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-617.

Key facts

Severity: High (CVSS 3.x base score 8.6)
EPSS exploit prediction: 10% (95th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-617
Affected product: Squid-cache Squid
Published: 2023-12-04
Last modified: 2026-06-17

Description

Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Due to an Incorrect Check of Function Return Value bug Squid is vulnerable to a Denial of Service attack against its Helper process management. This bug is fixed by Squid version 6.5. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Frequently asked questions

What is CVE-2023-49286?: Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Due to an Incorrect Check of Function Return Value bug Squid is vulnerable to a Denial of Service attack against its Helper process management. This bug is fixed by Squid version 6.5. Users are advised to upgrade. There are no known workarounds for this vulnerability.
How severe is CVE-2023-49286?: CVE-2023-49286 has a CVSS 3.x base score of 8.6, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2023-49286 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 10% (95th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-49286?: CVE-2023-49286 affects Squid-cache Squid. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-49286?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2023-49286 published?: CVE-2023-49286 was published on 2023-12-04 and last updated on 2026-06-17.

References

Affected products (1)

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

More vulnerabilities in Squid-cache Squid

CVE-2025-62168 — Critical (CVSS 10.0): Squid is a caching proxy for the Web. In Squid versions prior to 7.2, a failure to redact HTTP authentication…
CVE-2020-15049 — Critical (CVSS 9.9): An issue was discovered in http/ContentLengthInterpreter.cc in Squid before 4.12 and 5.x before 5.0.3. A Request…
CVE-2020-11945 — Critical (CVSS 9.8): An issue was discovered in Squid before 5.0.2. A remote attacker can replay a sniffed Digest Authentication nonce to…
CVE-2019-12519 — Critical (CVSS 9.8): An issue was discovered in Squid through 4.7. When handling the tag esi:when when ESI is enabled, Squid calls…
CVE-2019-12524 — Critical (CVSS 9.8): An issue was discovered in Squid through 4.7. When handling requests from users, Squid checks its rules to see if the…
CVE-2019-12526 — Critical (CVSS 9.8): An issue was discovered in Squid before 4.9. URN response handling in Squid suffers from a heap-based buffer overflow.…

All CVEs affecting Squid-cache Squid →

Other CWE-617 (Reachable Assertion) vulnerabilities

CVE-2020-3615 — Critical (CVSS 9.8): Valid deauth/disassoc frames is dropped in case if RMF is enabled and some rouge peer keep on sending rogue…
CVE-2019-9795 — Critical (CVSS 9.8): A vulnerability where type-confusion in the IonMonkey just-in-time (JIT) compiler could potentially be used by…
CVE-2026-31739 — High (CVSS 8.8): In the Linux kernel, the following vulnerability has been resolved: crypto: tegra - Add missing CRYPTO_ALG_ASYNC The…
CVE-2020-12417 — High (CVSS 8.8): Due to confusion about ValueTags on JavaScript Objects, an object may pass through the type barrier, resulting in…
CVE-2020-6623 — High (CVSS 8.8): stb stb_truetype.h through 1.22 has an assertion failure in stbtt__cff_get_index.
CVE-2020-6619 — High (CVSS 8.8): stb stb_truetype.h through 1.22 has an assertion failure in stbtt__buf_seek.

Browse all CWE-617 (Reachable Assertion) 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)