CVE-2021-27504: Texas Instruments devices running FREERTOS, malloc returns a valid pointer to a small buffer on extremely lar

Q: How do I fix CVE-2021-27504?

freertos: mitigate or apply the listed mitigation; simplelink cc13xx software development kit: upgrade to 4.40.00; simplelink cc26xx software development kit: upgrade to 4.40.00. Exact commands for each OS are on this page.

Q: Is CVE-2021-27504 being exploited?

CVE-2021-27504 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-2021-27504 affect?

CVE-2021-27504 affects freertos, simplelink cc13xx software development kit, simplelink cc26xx software development kit. Severity is high (CVSS 7.4). Texas Instruments devices running FREERTOS, malloc returns a valid pointer to a small buffer on extremely large values, which can trigger an integer overflow vulnerability in 'malloc' for FreeRTOS, resulting in code execution.

Q: How urgent is CVE-2021-27504?

Priority 36/100. High severity; On your watchlist

Routine

HIGH 7.4WATCHLISTMITIGATEUPGRADEUPGRADE

CVE-2021-27504 is a high-severity flaw (CVSS 7.4) affecting freertos, simplelink cc13xx software development kit, simplelink cc26xx software development kit. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Texas Instruments devices running FREERTOS, malloc returns a valid pointer to a small buffer on extremely large values, which can trigger an integer overflow vulnerability in 'malloc' for FreeRTOS, resulting in code execution.

Why this priority

High severity
On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score	7.4 (High)
Attack vector	Local
Attack complexity	High
Privileges needed	None
User interaction	None
EPSS exploit chance	0.3% (top 80%)
CISA exploited list	No
Weakness	CWE-190
Published	2023-11-21
Last modified	2026-06-17

Publisher (CNA): ICS-CERT · Vendor: amazon · ti

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

Am I affected?

Timeline

2023-11-21 18:15 UTCPublished CVE record published
2026-06-17 03:44 UTCUpdated Record last modified

amazon freertos MITIGATE

Affected: 10.4.1

Fixed in: no fixed release known

Safe to downgrade to: a release before 10.4.1

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

ti simplelink cc13xx software development kit UPGRADE

Affected: < 4.40.00

Fixed in: 4.40.00

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy simplelink-cc13xx-software-development-kit || rpm -q simplelink-cc13xx-software-development-kit || simplelink-cc13xx-software-development-kit --version

2. UPGRADE to 4.40.00 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade simplelink-cc13xx-software-development-kit

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade simplelink-cc13xx-software-development-kit

Note

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

ti simplelink cc26xx software development kit UPGRADE

Affected: < 4.40.00

Fixed in: 4.40.00

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy simplelink-cc26xx-software-development-kit || rpm -q simplelink-cc26xx-software-development-kit || simplelink-cc26xx-software-development-kit --version

2. UPGRADE to 4.40.00 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade simplelink-cc26xx-software-development-kit

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade simplelink-cc26xx-software-development-kit

Note

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

ti simplelink cc32xx software development kit UPGRADE

Affected: < 4.10.03

Fixed in: 4.10.03

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy simplelink-cc32xx-software-development-kit || rpm -q simplelink-cc32xx-software-development-kit || simplelink-cc32xx-software-development-kit --version

2. UPGRADE to 4.10.03 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade simplelink-cc32xx-software-development-kit

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade simplelink-cc32xx-software-development-kit

Note

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

ti simplelink msp432e401y MITIGATE

Affected: all versions

Fixed in: no fixed release known

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy simplelink-msp432e401y || rpm -q simplelink-msp432e401y || simplelink-msp432e401y --version

No fixed or unaffected release known

Apply the vendor mitigation from the advisory, disable the affected feature, or restrict network access.

ti simplelink msp432e411y MITIGATE

Affected: all versions

Fixed in: no fixed release known

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy simplelink-msp432e411y || rpm -q simplelink-msp432e411y || simplelink-msp432e411y --version

No fixed or unaffected release known

Apply the vendor mitigation from the advisory, disable the affected feature, or restrict network access.

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-2021-27504?

freertos: mitigate or apply the listed mitigation; simplelink cc13xx software development kit: upgrade to 4.40.00; simplelink cc26xx software development kit: upgrade to 4.40.00. Exact commands for each OS are on this page.

Is CVE-2021-27504 being exploited?

CVE-2021-27504 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-2021-27504 affect?

CVE-2021-27504 affects freertos, simplelink cc13xx software development kit, simplelink cc26xx software development kit. Severity is high (CVSS 7.4). Texas Instruments devices running FREERTOS, malloc returns a valid pointer to a small buffer on extremely large values, which can trigger an integer overflow vulnerability in 'malloc' for FreeRTOS, resulting in code execution.

How urgent is CVE-2021-27504?

Priority 36/100. High severity; On your watchlist

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References

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