How severe is CVE-2026-70427?

CVE-2026-70427 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2026-70427 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-70427?

CVE-2026-70427 primarily affects Jenkins. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-70427?

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

When was CVE-2026-70427 published?

CVE-2026-70427 was published on 2026-08-05 and last updated on 2026-09-08.

CVE-2026-70427

CVE-2026-70427 is a medium-severity vulnerability in Jenkins with a CVSS 3.x base score of 4.3. 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-59.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
EPSS exploit prediction: 0% (26th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-59
Affected product: Jenkins
Published: 2026-08-05
Last modified: 2026-09-08

Description

Jenkins 2.575 and earlier, LTS 2.568.1 and earlier does not safely handle symbolic links with effectively empty names during the extraction of `.tar` and `.tar.gz` archives, allowing attackers able to control agent processes to provide crafted archives to the controller to write files to arbitrary locations on the file system, restricted only by file system access permissions of the user running Jenkins.

Frequently asked questions

What is CVE-2026-70427?: Jenkins 2.575 and earlier, LTS 2.568.1 and earlier does not safely handle symbolic links with effectively empty names during the extraction of `.tar` and `.tar.gz` archives, allowing attackers able to control agent processes to provide crafted archives to the controller to write files to arbitrary locations on the file system, restricted only by file system access permissions of the user running Jenkins.
How severe is CVE-2026-70427?: CVE-2026-70427 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2026-70427 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-70427?: CVE-2026-70427 primarily affects Jenkins. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-70427?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-70427 published?: CVE-2026-70427 was published on 2026-08-05 and last updated on 2026-09-08.

References

https://www.jenkins.io/security/advisory/2026-08-05/#SECURITY-3930

Affected products (2)

cpe:2.3:a:jenkins:jenkins:*:*:*:*:lts:*:*:*
cpe:2.3:a:jenkins:jenkins:*:*:*:*:-:*:*:*

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Threat intelligence

Threat-intel indicators referencing this CVE:

116.196.119.94 (ipv4-addr)
47.254.36.213 (ipv4-addr)