CVE Intelligence
High Memory corruption

CVE-2026-21897 — CryptoLib Has Out-of-Bounds Write in Crypto_Config_Add_Gvcid_Managed_Parameters

CryptoLib provides a software-only solution using the CCSDS Space Data Link Security Protocol - Extended Procedures (SDLS-EP) to secure communications between a spacecraft running the core Flight System (cFS) and a ground station. Prior to version 1.4.3, the Crypto_Config_Add_Gvcid_Managed_Parameters function only checks whether gvcid_counter > GVCID_MAN_PARAM_SIZE. As a result, it allows up to the 251st entry, which causes a write past the end of the array, overwriting gvcid_counter located immediately after gvcid_managed_parameters_array[250]. This leads to an out-of-bounds write, and the overwritten gvcid_counter may become an arbitrary value, potentially affecting the parameter lookup/registration logic that relies on it. This issue has been patched in version 1.4.3.

Published Jan 9, 2026 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: GitHub_M

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 0.3% (30-day exploitation probability)+3
  • Technical severity (high)+6
  • Automatable exploitation (SSVC)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.28%
ahead of 19% of scored CVEs · Oct 14, 2026
Affects
Nasa
Cryptolib
CVSS base
7.3
High · 2 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
None
none · proof-of-concept · active
Automatable
Yes
can an attacker script the kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Nasa Cryptolib).
  2. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  3. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  4. Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Nasa Cryptolib < 1.4.3 Vulnerable NIST National Vulnerability Database
Nasa Cryptolib version < 1.4.3 Vulnerable CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
Low

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
7.3 CVSS 3.1 High 3.9 3.4 security-advisories@github.com via NIST National Vulnerability Database
7.3 CVSS 3.1 High — — GitHub_M via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L (score shown at the top: security-advisories@github.com)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-787 · Out-of-bounds Write

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.28%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
  • Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
web/proxy/WAF logsnetwork IDS/IPSendpoint telemetry (EDR)crash dumps

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · nasa/cryptolib
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 13, 2026
  • CVSS changed · 7.3
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · → Analyzed
    Oct 13, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVE published
    Jan 9, 2026 · GitHub_M

Source activity

Repeated readings are counted rather than listed.

  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

2 on the record

Elsewhere on this site

Nasa
every CVE for this vendor
CWE-787
other pages naming this weakness

Related CVEs (same products)

  • High CVE-2026-22697 CryptoLib Has Heap Buffer Overflow Vulnerability in KMC Base64 Decode Handling (KMC JSON base64ciphertext/base64cleartext) Jan 9, 2026
  • Medium CVE-2026-21899 CryptoLib has an out-of-bounds read and crash vulnerability when decoding an empty Base64url string Jan 9, 2026
  • Medium CVE-2026-21900 CryptoLib Has Out-of-Bounds Read in KMC Encrypt Metadata Parsing via Flawed strtok Pattern Jan 9, 2026
  • High CVE-2026-22023 CryptoLib Has Out-of-Bounds Read in KMC AEAD Encrypt Metadata Parsing via Flawed strtok Pattern Jan 9, 2026
  • Medium CVE-2026-22024 CryptoLib Memory Leak in KMC Encrypt Function Leads to Resource Exhaustion Jan 9, 2026
  • Low CVE-2026-22025 CryptoLib Memory Leak on HTTP Error Response in KMC Client Jan 9, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No fixed version, patch or mitigation documented.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-21897 is "CryptoLib Has Out-of-Bounds Write in Crypto_Config_Add_Gvcid_Managed_Parameters", rated High. It affects Cryptolib (Nasa); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.3 describes technical severity. EPSS 0.28% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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