How severe is CVE-2026-34356?

CVE-2026-34356 has a CVSS 3.x base score of 7.5, 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-2026-34356 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-34356?

CVE-2026-34356 affects Apache Http Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-34356?

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.

Does CVE-2026-34356 have an EU (EUVD) identifier?

Yes. CVE-2026-34356 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-35089.

When was CVE-2026-34356 published?

CVE-2026-34356 was published on 2026-06-08 and last updated on 2026-06-17.

CVE-2026-34356

CVE-2026-34356 is a high-severity vulnerability in Apache Http Server with a CVSS 3.x base score of 7.5. 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-122.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (48th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-35089
Weakness: CWE-122
Affected product: Apache Http Server
Published: 2026-06-08
Last modified: 2026-06-17

Description

Heap-based Buffer Overflow vulnerability in Apache HTTP Server with malicious backend servers and ProxyPassReverseCookie* This issue affects Apache HTTP Server: from 2.4.0 through 2.4.67. Users are recommended to upgrade to version 2.4.68, which fixes the issue.

Frequently asked questions

What is CVE-2026-34356?: Heap-based Buffer Overflow vulnerability in Apache HTTP Server with malicious backend servers and ProxyPassReverseCookie* This issue affects Apache HTTP Server: from 2.4.0 through 2.4.67. Users are recommended to upgrade to version 2.4.68, which fixes the issue.
How severe is CVE-2026-34356?: CVE-2026-34356 has a CVSS 3.x base score of 7.5, 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-2026-34356 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-34356?: CVE-2026-34356 affects Apache Http Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-34356?: 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.
Does CVE-2026-34356 have an EU (EUVD) identifier?: Yes. CVE-2026-34356 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-35089.
When was CVE-2026-34356 published?: CVE-2026-34356 was published on 2026-06-08 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*

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Threat intelligence

Threat-intel indicators referencing this CVE:

50.255.62.89 (ipv4-addr)
147.15.15.226 (ipv4-addr)
45.84.120.3 (ipv4-addr)
77.90.185.88 (ipv4-addr)
77.90.185.87 (ipv4-addr)
74.87.117.150 (ipv4-addr)
50.35.168.148 (ipv4-addr)
49.0.24.107 (ipv4-addr)