How severe is CVE-2026-100277?

CVE-2026-100277 has a CVSS 3.x base score of 8.9, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability low.

Is CVE-2026-100277 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-100277?

CVE-2026-100277 affects Jetbrains Youtrack. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-100277?

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-2026-100277 published?

CVE-2026-100277 was published on 2026-09-30 and last updated on 2026-10-02.

CVE-2026-100277

CVE-2026-100277 is a high-severity vulnerability in Jetbrains Youtrack with a CVSS 3.x base score of 8.9. 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-863.

Key facts

Severity: High (CVSS 3.x base score 8.9)
EPSS exploit prediction: 0% (19th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-863
Affected product: Jetbrains Youtrack
Published: 2026-09-30
Last modified: 2026-10-02

Description

In JetBrains YouTrack before 2026.2.19197 account takeover was possible by replaying a notification signature

Frequently asked questions

What is CVE-2026-100277?: In JetBrains YouTrack before 2026.2.19197 account takeover was possible by replaying a notification signature
How severe is CVE-2026-100277?: CVE-2026-100277 has a CVSS 3.x base score of 8.9, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability low.
Is CVE-2026-100277 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-100277?: CVE-2026-100277 affects Jetbrains Youtrack. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-100277?: 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-2026-100277 published?: CVE-2026-100277 was published on 2026-09-30 and last updated on 2026-10-02.

References

https://www.jetbrains.com/privacy-security/issues-fixed/

Affected products (1)

cpe:2.3:a:jetbrains:youtrack:*:*:*:*:*:*:*:*

More vulnerabilities in Jetbrains Youtrack

CVE-2026-62422 — Critical (CVSS 10.0): In JetBrains YouTrack before 2026.1.13757, 2025.3.148033, 2025.2.148048, 2025.1.148120, 2024.3.148430, 2024.2.148429…
CVE-2022-24442 — Critical (CVSS 9.8): JetBrains YouTrack before 2021.4.40426 was vulnerable to SSTI (Server-Side Template Injection) via FreeMarker templates.
CVE-2021-43185 — Critical (CVSS 9.8): JetBrains YouTrack before 2021.3.23639 is vulnerable to Host header injection.
CVE-2021-25770 — Critical (CVSS 9.8): In JetBrains YouTrack before 2020.5.3123, server-side template injection (SSTI) was possible, which could lead to code…
CVE-2019-12852 — Critical (CVSS 9.8): An SSRF attack was possible on a JetBrains YouTrack server. The issue (1 of 2) was fixed in JetBrains YouTrack…
CVE-2019-12867 — Critical (CVSS 9.8): Certain actions could cause privilege escalation for issue attachments in JetBrains YouTrack. The issue was fixed in…

All CVEs affecting Jetbrains Youtrack →

Other CWE-863 (Incorrect Authorization) vulnerabilities

CVE-2026-75745 — Critical (CVSS 10.0): Adobe Experience Manager Forms JEE is affected by an Incorrect Authorization vulnerability that could result in…
CVE-2026-75723 — Critical (CVSS 10.0): Adobe Campaign Classic (ACC) is affected by an Incorrect Authorization vulnerability that could result in arbitrary…
CVE-2026-69555 — Critical (CVSS 10.0): Incorrect authorization in Azure Arc allows an unauthorized attacker to elevate privileges over a network.
CVE-2026-71398 — Critical (CVSS 10.0): Adobe Campaign Classic (ACC) is affected by an Incorrect Authorization vulnerability that could result in arbitrary…
CVE-2026-27302 — Critical (CVSS 10.0): Adobe Campaign Classic (ACC) is affected by an Incorrect Authorization vulnerability that could result in arbitrary…
CVE-2026-48449 — Critical (CVSS 10.0): Adobe Campaign Classic (ACC) is affected by an Incorrect Authorization vulnerability that could result in arbitrary…

Browse all CWE-863 (Incorrect Authorization) vulnerabilities →