Skip to content
Noroxi
NVD / CVE Program· CNA mitre

CVE-2020-29573: sysdeps/i386/ldbl2mpn.c in the GNU C Library (aka glibc or libc6) before 2.23 on x86 targets has a stack-based buffer overflow if the input

Noroxi assessment

Priority: Monitor (action score 31/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 2.7% (FIRST EPSS); higher than 85.9% of all records.
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: glibc (Debian:12) 2.23-1; glibc (openSUSE:Leap 15.2) 2.26-lp152.26.6.1; glibc-testsuite-src (openSUSE:Leap 15.2) 2.26-lp152.26.6.1.
  • Mentioned 2 times in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to glibc (Debian:12) 2.23-1; glibc (openSUSE:Leap 15.2) 2.26-lp152.26.6.1; glibc-testsuite-src (openSUSE:Leap 15.2) 2.26-lp152.26.6.1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

sysdeps/i386/ldbl2mpn.c in the GNU C Library (aka glibc or libc6) before 2.23 on x86 targets has a stack-based buffer overflow if the input to any of the printf family of functions is an 80-bit long double with a non-canonical bit pattern, as seen when passing a \x00\x04\x00\x00\x00\x00\x00\x00\x00\x04 value to sprintf. NOTE: the issue does not affect glibc by default in 2016 or later (i.e., 2.23 or later) because of commits made in 2015 for inlining of C99 math functions through use of GCC built-ins. In other words, the reference to 2.23 is intentional despite the mention of "Fixed for glibc 2.33" in the 26649 reference.

HighCVSS 7.5 · v3.1—No exploit Fix available
Published
Dec 6, 2020
Updated
Oct 14, 2026
EPSS
2.7% · 85th percentile

Report tools

JSON

Action score

31

Monitor

Low priority for now.

CVSS
30 / 40 · 7.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
1 / 30 · 2.7%

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2020-29573

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

One daily email digest (06:00 UTC); connect a webhook for KEV listings and weaponized exploits instantly.

Your free account also gets you

Running WordPress? Scan your site free with WP Lens

  • Stack alerts: add the products and versions you run, get the new CVEs that affect them
  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools (3 a day without an account), an API key and MCP
  • All your scans in one panel: findings, what changed in the last scan, a report per domain or per client (PDF, share link)
All free tools

Sign up with email · Have an account? Sign in

Free account, no card. Unfollow any time.

Don't want an account? Get "Exploited this week" by email every MondayDon't want an account? RSS feed for gnu records

Running WordPress? Scan your site free with WP Lens

Is your version affected? Check it

Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

We use this product, ask for help

Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
gnuglibc
redhatenterprise linux
netappcloud backup
netappsolidfire baseboard management controller

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • gnu glibcbefore 2.23
  • netapp cloud backupall versions
  • netapp solidfire baseboard management controllerall versions
  • redhat enterprise linux7.0

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12glibcbefore 2.23-12.23-1
openSUSE:Leap 15.2glibcbefore 2.26-lp152.26.6.12.26-lp152.26.6.1
openSUSE:Leap 15.2glibc-testsuite-srcbefore 2.26-lp152.26.6.12.26-lp152.26.6.1
Red Hat:enterprise_linux:7::clientglibcbefore 0:2.17-322.el7_90:2.17-322.el7_9
Red Hat:enterprise_linux:7::clientglibc-commonbefore 0:2.17-322.el7_90:2.17-322.el7_9
Red Hat:enterprise_linux:7::clientglibc-debuginfobefore 0:2.17-322.el7_90:2.17-322.el7_9
Red Hat:enterprise_linux:7::clientglibc-debuginfo-commonbefore 0:2.17-322.el7_90:2.17-322.el7_9
Red Hat:enterprise_linux:7::clientglibc-develbefore 0:2.17-322.el7_90:2.17-322.el7_9
Red Hat:enterprise_linux:7::clientglibc-headersbefore 0:2.17-322.el7_90:2.17-322.el7_9
Red Hat:enterprise_linux:7::clientglibc-staticbefore 0:2.17-322.el7_90:2.17-322.el7_9
Red Hat:enterprise_linux:7::clientglibc-utilsbefore 0:2.17-322.el7_90:2.17-322.el7_9
Red Hat:enterprise_linux:7::clientnscdbefore 0:2.17-322.el7_90:2.17-322.el7_9
Red Hat:rhel_aus:7.4::serverglibcbefore 0:2.17-196.el7_4.40:2.17-196.el7_4.4
Red Hat:rhel_aus:7.4::serverglibc-commonbefore 0:2.17-196.el7_4.40:2.17-196.el7_4.4
Red Hat:rhel_aus:7.4::serverglibc-debuginfobefore 0:2.17-196.el7_4.40:2.17-196.el7_4.4
Red Hat:rhel_aus:7.4::serverglibc-debuginfo-commonbefore 0:2.17-196.el7_4.40:2.17-196.el7_4.4
Red Hat:rhel_aus:7.4::serverglibc-develbefore 0:2.17-196.el7_4.40:2.17-196.el7_4.4
Red Hat:rhel_aus:7.4::serverglibc-headersbefore 0:2.17-196.el7_4.40:2.17-196.el7_4.4
Red Hat:rhel_aus:7.4::serverglibc-staticbefore 0:2.17-196.el7_4.40:2.17-196.el7_4.4
Red Hat:rhel_aus:7.4::serverglibc-utilsbefore 0:2.17-196.el7_4.40:2.17-196.el7_4.4
Red Hat:rhel_aus:7.4::servernscdbefore 0:2.17-196.el7_4.40:2.17-196.el7_4.4
Red Hat:rhel_aus:7.6::serverglibcbefore 0:2.17-260.el7_6.90:2.17-260.el7_6.9
Red Hat:rhel_aus:7.6::serverglibc-commonbefore 0:2.17-260.el7_6.90:2.17-260.el7_6.9
Red Hat:rhel_aus:7.6::serverglibc-debuginfobefore 0:2.17-260.el7_6.90:2.17-260.el7_6.9

+19

Same product

gnu: all records

Other highest-scoring records for the same primary product.

  • CVE-2023-4911Glibc: buffer overflow in ld.so leading to privilege escalationKEV
    80Now
  • CVE-2015-0235Heap-based buffer overflow in the __nss_hostname_digits_dots function in glibc 2.2, and other 2.x versions before 2.18, allows context-depen
    68This week
  • CVE-2015-7547Multiple stack-based buffer overflows in the (1) send_dg and (2) send_vc functions in the libresolv library in the GNU C Library (aka glibc
    60This week

Published before and after this one in the same product

  • ← EarlierCVE-1999-0199Oct 6, 2020 · manual/search.texi in the GNU C Library (aka glibc) before 2.2 lacks a statement about the unspecified tdelete return value upon deletion of
    40Plan
  • ← EarlierCVE-2020-29562Dec 4, 2020 · The iconv function in the GNU C Library (aka glibc or libc6) 2.30 to 2.32, when converting UCS4 text containing an irreversible character, f
    20Monitor
  • Later →CVE-2019-25013Jan 4, 2021 · The iconv feature in the GNU C Library (aka glibc or libc6) through 2.32, when processing invalid multi-byte input sequences in the EUC-KR e
    24Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
debian:glibc2.23-1 · Debian:12Package registry (OSV)
opensuse:glibc2.26-lp152.26.6.1 · openSUSE:Leap 15.2Package registry (OSV)
opensuse:glibc-testsuite-src2.26-lp152.26.6.1 · openSUSE:Leap 15.2Package registry (OSV)
red hat:glibc0:2.17-322.el7_9 · Red Hat:enterprise_linux:7::clientPackage registry (OSV)
red hat:glibc-common0:2.17-322.el7_9 · Red Hat:enterprise_linux:7::clientPackage registry (OSV)
red hat:glibc-debuginfo0:2.17-322.el7_9 · Red Hat:enterprise_linux:7::clientPackage registry (OSV)
red hat:glibc-debuginfo-common0:2.17-322.el7_9 · Red Hat:enterprise_linux:7::clientPackage registry (OSV)
red hat:glibc-devel0:2.17-322.el7_9 · Red Hat:enterprise_linux:7::clientPackage registry (OSV)
red hat:glibc-headers0:2.17-322.el7_9 · Red Hat:enterprise_linux:7::clientPackage registry (OSV)
red hat:glibc-static0:2.17-322.el7_9 · Red Hat:enterprise_linux:7::clientPackage registry (OSV)
red hat:glibc-utils0:2.17-322.el7_9 · Red Hat:enterprise_linux:7::clientPackage registry (OSV)
red hat:nscd0:2.17-322.el7_9 · Red Hat:enterprise_linux:7::clientPackage registry (OSV)
suse:glibc2.26-13.56.1 · SUSE:Linux Enterprise Module for Basesystem 15 SP2Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

CWE-787 · Out-of-bounds Write

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (4 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records