Security Digest · Vulnerability record
CVE-2025-9287: cipher-base is missing type checks, leading to hash rewind and passing on crafted data
Improper Input Validation vulnerability in cipher-base allows Input Data Manipulation.This issue affects cipher-base: through 1.0.4.
CVSS 9.1 Critical EPSS 0.5% · p45
Should you act?
Critical and remotely reachable
No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.
- Not in CISA KEV, but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 0.5%, percentile 45: FIRST’s model estimates a 0.5% chance of exploitation activity in the next 30 days, higher than 45% of all scored CVEs (low). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes
cipher-base(npm) <= 1.0.4, fixed in 1.0.5. Check your lockfile, including transitive dependencies.
What it is
Improper Input Validation vulnerability in cipher-base allows Input Data Manipulation.This issue affects cipher-base: through 1.0.4.
From the GitHub advisory
Summary
This affects e.g. create-hash (and crypto-browserify), so I'll describe the issue against that package Also affects create-hmac and other packages
Node.js createHash works only on strings or instances of Buffer, TypedArray, or DataView.
Missing input type checks (in npm create-hash polyfill of Node.js createHash) can allow types other than a well-formed Buffer or string, resulting in invalid values, hanging and rewinding the hash state (including turning a tagged hash into an untagged hash), or other generally undefined behaviour.
Details
Weakness type: CWE-20.
Product: cipher-base (npm) · Assigned by: harborist · Published: 2025-08-20
Affected and fixed versions
| Ecosystem | Package | Vulnerable | First fixed |
|---|---|---|---|
| npm | cipher-base | <= 1.0.4 | 1.0.5 |
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| cipher-base | <= 1.0.4 |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| harborist | 4.0 | 9.1 Critical | CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:H/VA:H/SC:H/SI:H/SA:N |
| GitHub | 4.0 | 9.1 | CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:H/VA:H/SC:H/SI:H/SA:N |
- Attack vector: network (remotely reachable)
- Attack complexity: high (needs special conditions)
- Attack requirements: present (depends on deployment conditions)
- Privileges required: none (no login)
- User interaction: none
CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.
Exploitation and urgency
- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc, automatable no, technical impact partial.
- FIRST EPSS (model of 2026-10-21): 0.55% probability of exploitation activity in the next 30 days; percentile 45.
Timeline
- — CVE record published by harborist
- — GitHub-reviewed advisory GHSA-cpq7-6gpm-g9rc published (critical)
- — CVE record last updated
Sources and references
Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.
Vendor and project advisories, patches
- github.com github.com
- github.com github.com
Vulnerability records
- GitHub Advisory GHSA-cpq7-6gpm-g9rc github.com
- CVE.org record CVE-2025-9287 cve.org
- NVD entry CVE-2025-9287 nvd.nist.gov
Other references from the CVE record and advisory
- lists.debian.org lists.debian.org
- github.com github.com