Cyber Resilience

CVE-2023-51451

SSRF in Sentry Symbolicator 0.3.3 – 23.12.1

Published
22 December 2023
Modified
21 November 2024
Patch / advisory
CVSS Score v3.1 4.3
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
EPSS Score 0.0047 38th percentile
Risk Priority 37 floored blend · peak EPSS

Summary

CVE-2023-51451 is a medium-severity SSRF (CWE-918) vulnerability in Sentry Symbolicator. Its CVSS base score is 4.3 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 38th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Symbolicator is a service used in Sentry. Starting in Symbolicator version 0.3.3 and prior to version 21.12.1, an attacker could make Symbolicator send GET HTTP requests to arbitrary URLs with internal IP addresses by using an invalid protocol. The responses…

more

of those requests could be exposed via Symbolicator's API. In affected Sentry instances, the data could be exposed through the Sentry API and user interface if the attacker has a registered account. The issue has been fixed in Symbolicator release 23.12.1, Sentry self-hosted release 23.12.1, and has already been mitigated on sentry.io on December 18, 2023. If updating is not possible, some other mitigations are available. One may disable JS processing by toggling the option `Allow JavaScript Source Fetching` in `Organization Settings > Security & Privacy` and/or disable all untrusted public repositories under `Project Settings > Debug Files`. Alternatively, if JavaScript and native symbolication are not required, disable Symbolicator completely in `config.yml`.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-49094Same product: Sentry Symbolicator
CVE-2024-24829Same product class: VPN / SSL gateway
CVE-2023-46729Same product class: VPN / SSL gateway
CVE-2024-45605Same product class: VPN / SSL gateway
CVE-2026-26004Same product class: VPN / SSL gateway
CVE-2024-45606Same product class: VPN / SSL gateway
CVE-2025-0292Same product class: VPN / SSL gateway
CVE-2026-0285Same product class: VPN / SSL gateway
CVE-2024-21893Same product class: VPN / SSL gateway
CVE-2024-5917Same product class: VPN / SSL gateway

Affected Assets

sentry
symbolicator
0.3.3 — 23.12.1

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V1.3.6
  • V1.5.3
  • V5.3.2
  • V10.4.7

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-918

Penetration testing attempts server-side requests to internal resources, identifying SSRF weaknesses for remediation.

addresses: CWE-918

Outbound connections to external resources can be monitored and limited at the boundary, reducing SSRF impact.

addresses: CWE-918

Validates server-side URLs and resource references to block SSRF attempts.

addresses: CWE-918

Detects server-side request forgery through monitoring of unexpected outbound connections.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure development practices directly include input validation and destination allow-listing that prevent SSRF.

DE.CM-09 partial match
prevents

Runtime monitoring of web applications and services can detect anomalous outbound requests indicative of SSRF.

ID.RA-01 partial match
prevents

Vulnerability identification processes can discover and record SSRF flaws in web applications.

PR.IR-01 partial match
prevents

Network segmentation and egress controls can limit the damage from successful SSRF requests.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

Operational threat data describing SSRF campaigns can be used to tighten outbound-request allow-lists and detection rules before attackers exploit them.

References