Security Resilience

CVE-2026-35461

SSRF in Papra ≤ 26.4.0

Public PoCSSRF
Published
07 April 2026
Modified
24 April 2026
Patch / advisory
View advisory
CVSS Score v3.1 5.0
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N
EPSS Score 0.0030 22th percentile
Risk Priority 38 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). EPSS scores by FIRST (EPSS SIG), generated by Empirical Security. Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2026-35461 is a medium-severity SSRF (CWE-918) vulnerability in Papra Papra. Its CVSS base score is 5.0 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 22th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to AC-4 (Information Flow Enforcement) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

A01:2025 Broken Access Control

EU & UK References

Vulnerability Data

Papra is a minimalistic document management and archiving platform. Prior to 26.4.0, the Papra webhook system allows authenticated users to register arbitrary URLs as webhook endpoints with no validation of the destination address. The server makes outbound HTTP POST requests…

more

to registered URLs, including localhost, internal network ranges, and cloud provider metadata endpoints, on every document event. This vulnerability is fixed in 26.4.0.

CWE(s)
CWE-918

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.
attack.mitre.org →
T1584 Compromise Infrastructure Resource Development
Adversaries may compromise third-party infrastructure that can be used during targeting.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-35460Same product: Papra Papra
CVE-2026-35462Same product: Papra Papra
CVE-2024-43989Shared CWE-918
CVE-2025-47791Shared CWE-918
CVE-2026-18378Shared CWE-918
CVE-2026-92719Shared CWE-918
CVE-2025-10211Shared CWE-918
CVE-2025-9522Shared CWE-918
CVE-2026-86771Shared CWE-918
CVE-2026-62857Shared CWE-918

Affected Assets

papra
papra
≤ 26.4.0

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

Mitigating Controls (NIST 800-53 r5) AI

AC-4 Information Flow Enforcement good match

Information flow enforcement can restrict which destinations the server is allowed to contact on behalf of users.

SI-10 Information Input Validation good match

Input validation directly stops untrusted URLs from being accepted and fetched without destination checks.

SC-7 Boundary Protection partial match

Boundary protection limits the network reach of server-initiated requests even if SSRF occurs.

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
blocks

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

DE.CM-09 partial match
blocks

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

ID.RA-01 partial match
blocks

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

PR.IR-01 partial match
blocks

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

References