How severe is CVE-2026-34355?

CVE-2026-34355 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-2026-34355 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-34355?

CVE-2026-34355 affects Apache Http Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-34355?

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-2026-34355 have an EU (EUVD) identifier?

Yes. CVE-2026-34355 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-35097.

When was CVE-2026-34355 published?

CVE-2026-34355 was published on 2026-06-08 and last updated on 2026-07-02.

CVE-2026-34355

CVE-2026-34355 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% (52nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-35097
Weakness: CWE-122
Affected product: Apache Http Server
Published: 2026-06-08
Last modified: 2026-07-02

Description

A buffer overflow in mod_proxy_html in Apache HTTP Server 2.4.67 and earlier allows an attack by an untrusted backend. Users are recommended to upgrade to version 2.4.68, which fixes this issue.

Frequently asked questions

What is CVE-2026-34355?: A buffer overflow in mod_proxy_html in Apache HTTP Server 2.4.67 and earlier allows an attack by an untrusted backend. Users are recommended to upgrade to version 2.4.68, which fixes this issue.
How severe is CVE-2026-34355?: CVE-2026-34355 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-2026-34355 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-34355?: CVE-2026-34355 affects Apache Http Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-34355?: 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-2026-34355 have an EU (EUVD) identifier?: Yes. CVE-2026-34355 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-35097.
When was CVE-2026-34355 published?: CVE-2026-34355 was published on 2026-06-08 and last updated on 2026-07-02.

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)