Cyber Resilience

CVE-2025-27508

Crypto Weakness

Published
05 March 2025
Modified
15 April 2026
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
EPSS Score 0.0020 10th percentile
Risk Priority 56 floored blend · peak EPSS

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

Summary

CVE-2025-27508 is a high-severity Use of a Broken or Risky Cryptographic Algorithm (CWE-327) vulnerability. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Adversary-in-the-Middle (T1557); ranked at the 10th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SC-13 (Cryptographic Protection) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2025-27508 affects Emissary, a peer-to-peer (P2P) based data-driven workflow engine developed by the National Security Agency. The vulnerability resides in the ChecksumCalculator class, which supports hashing and checksum generation using algorithms that are no longer recommended for secure cryptographic applications, such as SHA-1, CRC32, and SSDEEP. While these may suffice for non-security-critical tasks, their use in scenarios requiring strong cryptographic integrity can lead to risks like hash collisions or weak verification, tracked under CWE-327 (Broken Cryptographic Algorithms). The issue carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N) and was published on March 5, 2025.

Attackers can exploit this vulnerability remotely over the network with low complexity, requiring no privileges, user interaction, or special setup. Exploitation targets the integrity (I:H) aspect, potentially allowing adversaries to manipulate data by generating collisions or bypassing checksum validations in Emissary workflows, without impacting confidentiality or availability. Any unauthenticated network actor interacting with Emissary instances using the affected ChecksumCalculator could achieve this, compromising the trustworthiness of data processing in P2P environments.

The GitHub security advisory (GHSA-hw43-fcmm-3m5g) and associated commit (da3a81a8977577597ff2a944820a5ae4e9762368) confirm the fix in Emissary version 8.24.0, recommending immediate upgrades to eliminate the weak algorithms. Practitioners should review deployments for prior versions and audit usage of ChecksumCalculator to ensure it aligns with security requirements.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Emissary is a P2P based data-driven workflow engine. The ChecksumCalculator class within allows for hashing and checksum generation, but it includes or defaults to algorithms that are no longer recommended for secure cryptographic use cases (e.g., SHA-1, CRC32, and SSDEEP).…

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These algorithms, while possibly valid for certain non-security-critical tasks, can expose users to security risks if used in scenarios where strong cryptographic guarantees are required. This issue is fixed in 8.24.0.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1557 Adversary-in-the-Middle Credential Access
Adversaries may attempt to position themselves between two or more networked devices using an adversary-in-the-middle (AiTM) technique to support follow-on behaviors such as [Network Sniffing](https://attack.
T1040 Network Sniffing Credential Access
Adversaries may passively sniff network traffic to capture information about an environment, including authentication material passed over the network.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-37464Shared CWE-327
CVE-2023-30994Shared CWE-327
CVE-2024-4765Shared CWE-327
CVE-2023-36608Shared CWE-327
CVE-2024-39583Shared CWE-327
CVE-2024-29175Shared CWE-327
CVE-2023-41927Shared CWE-327
CVE-2023-22812Shared CWE-327
CVE-2025-43891Shared CWE-327
CVE-2026-40996Shared CWE-327

Affected Assets

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 4 hardening rules · 4 OS baselines
Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

SC-13 requires selection and implementation of specific cryptography types, directly stopping use of broken algorithms.

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.DS-01 partial match
prevents

PR.DS-01 promotes encryption for data-at-rest but never requires strong algorithms, leaving CWE-327 fully possible; the weakness is also far broader than data-at-rest so one narrow control removes none of its total risk.

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

Mandating approved algorithms, cipher strength and usage standards directly stops the selection of broken or weak cryptographic primitives that attackers can exploit.

prevents

The explicit call-out of cryptography-related legal constraints (import/export, key escrow, digital-signature validity) reduces the likelihood that an organization will adopt broken or non-compliant cryptographic algorithms that violate those rules.

prevents

Access to current specialist guidance and early vulnerability alerts enables timely replacement of broken or risky cryptographic algorithms with stronger alternatives.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (1 rule)
  • V-248524 OL 8 must implement NIST FIPS-validated cryptography for the following: To provision digital signatures, to generate cryptographic hashes, and to protect data requiring data-at-rest protections in accordance with applicable federal laws, Executive Orders, directives, policies, regulations, and standards. prevents CWE-327
Windows 10 (1 rule)
  • V-220937 The system must be configured to prevent the storage of the LAN Manager hash of passwords. prevents CWE-327
Windows Server 2016 (1 rule)
  • V-225053 Windows Server 2016 must be configured to prevent the storage of the LAN Manager hash of passwords. prevents CWE-327
Windows Server 2019 (1 rule)
  • V-205654 Windows Server 2019 must be configured to prevent the storage of the LAN Manager hash of passwords. prevents CWE-327

References