CVE-2021-36762: An issue was discovered in HCC Embedded InterNiche NicheStack through 4.3

Q: How do I fix CVE-2021-36762?

nichestack: upgrade to 4.3. Exact commands for each OS are on this page.

Q: Is CVE-2021-36762 being exploited?

CVE-2021-36762 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2021-36762 affect?

CVE-2021-36762 affects nichestack. Severity is high (CVSS 7.5). An issue was discovered in HCC Embedded InterNiche NicheStack through 4.3. The tfshnd():tftpsrv.c TFTP packet processing function doesn't ensure that a filename is adequately '\0' terminated; therefore, a subsequent call to strlen for the f

Q: How urgent is CVE-2021-36762?

Priority 52/100. High severity; Remotely exploitable, no login, no user action

This month

HIGH 7.5REMOTEUPGRADE

CVE-2021-36762 is a high-severity flaw (CVSS 7.5) affecting nichestack. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

An issue was discovered in HCC Embedded InterNiche NicheStack through 4.3. The tfshnd():tftpsrv.c TFTP packet processing function doesn't ensure that a filename is adequately '\0' terminated; therefore, a subsequent call to strlen for the filename might read out of bounds of the protocol packet buffer (if no '\0' byte exists within a reasonable range).

Why this priority

High severity
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	7.5 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	2.3% (top 17%)
CISA exploited list	No
Published	2021-08-19
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: hcc-embedded

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2021-08-19 12:15 UTCPublished CVE record published
2026-06-17 03:59 UTCUpdated Record last modified

hcc-embedded nichestack UPGRADE

Affected: < 4.3

Fixed in: 4.3

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy nichestack || rpm -q nichestack || nichestack --version

2. UPGRADE to 4.3 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade nichestack

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade nichestack

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2021-36762?

nichestack: upgrade to 4.3. Exact commands for each OS are on this page.

Is CVE-2021-36762 being exploited?

CVE-2021-36762 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2021-36762 affect?

CVE-2021-36762 affects nichestack. Severity is high (CVSS 7.5). An issue was discovered in HCC Embedded InterNiche NicheStack through 4.3. The tfshnd():tftpsrv.c TFTP packet processing function doesn't ensure that a filename is adequately '\0' terminated; therefore, a subsequent call to strlen for the f

How urgent is CVE-2021-36762?

Priority 52/100. High severity; Remotely exploitable, no login, no user action

Related CVEs

CVE-2021-31401 HIGH 7.5 UPGRADE UPGRADE An issue was discovered in tcp_rcv() in nptcp.c in HCC embedded InterNiche 4.0.1
CVE-2021-31400 HIGH 7.5 UPGRADE An issue was discovered in tcp_pulloutofband() in tcp_in.c in HCC embedded InterNiche 4.0.1
CVE-2021-31228 HIGH 7.5 UPGRADE An issue was discovered in HCC embedded InterNiche 4.0.1
CVE-2021-31227 HIGH 7.5 UPGRADE An issue was discovered in HCC embedded InterNiche 4.0.1
CVE-2021-27565 HIGH 7.5 UPGRADE The web server in InterNiche NicheStack through 4.0.1 allows remote attackers to cause a denial of service (in

References

← Back to latest CVEs