How severe is CVE-2026-44603?

CVE-2026-44603 has a CVSS 3.x base score of 3.7, rated low severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2026-44603 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-2026-44603?

CVE-2026-44603 affects Torproject Tor. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-44603?

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

Does CVE-2026-44603 have an EU (EUVD) identifier?

Yes. CVE-2026-44603 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-28306.

When was CVE-2026-44603 published?

CVE-2026-44603 was published on 2026-05-07 and last updated on 2026-06-17.

CVE-2026-44603

CVE-2026-44603 is a low-severity vulnerability in Torproject Tor with a CVSS 3.x base score of 3.7. 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-193.

Key facts

Severity: Low (CVSS 3.x base score 3.7)
EPSS exploit prediction: 0% (26th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-28306
Weakness: CWE-193
Affected product: Torproject Tor
Published: 2026-05-07
Last modified: 2026-06-17

Description

Tor before 0.4.9.7 has an out-of-bounds read by one byte via a malformed BEGIN cell, aka TROVE-2026-007.

Frequently asked questions

What is CVE-2026-44603?: Tor before 0.4.9.7 has an out-of-bounds read by one byte via a malformed BEGIN cell, aka TROVE-2026-007.
How severe is CVE-2026-44603?: CVE-2026-44603 has a CVSS 3.x base score of 3.7, rated low severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2026-44603 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-2026-44603?: CVE-2026-44603 affects Torproject Tor. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-44603?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-44603 have an EU (EUVD) identifier?: Yes. CVE-2026-44603 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-28306.
When was CVE-2026-44603 published?: CVE-2026-44603 was published on 2026-05-07 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:torproject:tor:*:*:*:*:*:*:*:*

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