How severe is CVE-2026-4965?

CVE-2026-4965 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2026-4965 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-4965?

CVE-2026-4965 affects Letta. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-4965?

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-2026-4965 have an EU (EUVD) identifier?

Yes. CVE-2026-4965 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-16736.

When was CVE-2026-4965 published?

CVE-2026-4965 was published on 2026-03-27 and last updated on 2026-06-17.

CVE-2026-4965

CVE-2026-4965 is a high-severity vulnerability in Letta with a CVSS 3.x base score of 7.3. 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-94.

Key facts

Severity: High (CVSS 3.x base score 7.3)
CVSS v2: 7.5
CVSS v4: 5.5
EPSS exploit prediction: 1% (45th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-16736
Weakness: CWE-94
Affected product: Letta
Published: 2026-03-27
Last modified: 2026-06-17

Description

A vulnerability was detected in letta-ai letta 0.16.4. This issue affects the function resolve_type of the file letta/functions/ast_parsers.py of the component Incomplete Fix CVE-2025-6101. Performing a manipulation results in improper neutralization of directives in dynamically evaluated code. The attack can be initiated remotely. The exploit is now public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

Frequently asked questions

What is CVE-2026-4965?: A vulnerability was detected in letta-ai letta 0.16.4. This issue affects the function resolve_type of the file letta/functions/ast_parsers.py of the component Incomplete Fix CVE-2025-6101. Performing a manipulation results in improper neutralization of directives in dynamically evaluated code. The attack can be initiated remotely. The exploit is now public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
How severe is CVE-2026-4965?: CVE-2026-4965 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2026-4965 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-4965?: CVE-2026-4965 affects Letta. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-4965?: 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-2026-4965 have an EU (EUVD) identifier?: Yes. CVE-2026-4965 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-16736.
When was CVE-2026-4965 published?: CVE-2026-4965 was published on 2026-03-27 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:letta:letta:0.16.4:*:*:*:*:*:*:*

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