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NVD / CVE Program· CNA apache

CVE-2021-35940: Regression of CVE-2017-12613

Noroxi assessment

Priority: Monitor (action score 28/100)

  • 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: 1.1% (FIRST EPSS); higher than 67.7% of all records.
  • Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: apr (Alpine:v3.14) 1.7.0-r1; apr (Alpine:v3.16) 1.7.0-r2; apr (Debian:12) 1.7.0-7.

Low priority for now. Upgrade to apr (Alpine:v3.14) 1.7.0-r1; apr (Alpine:v3.16) 1.7.0-r2; apr (Debian:12) 1.7.0-7 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

An out-of-bounds array read in the apr_time_exp*() functions was fixed in the Apache Portable Runtime 1.6.3 release (CVE-2017-12613). The fix for this issue was not carried forward to the APR 1.7.x branch, and hence version 1.7.0 regressed compared to 1.6.3 and is vulnerable to the same issue.

HighCVSS 7.1 · v3.1—No exploit Fix available
Published
Aug 23, 2021
Updated
Jun 16, 2026
EPSS
1.1% · 67th percentile

Report tools

JSON

Action score

28

Monitor

Low priority for now.

CVSS
28 / 40 · 7.1 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 1.1%

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.

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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

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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.

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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
apacheportable runtime
oraclehttp server

Affected versions

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

  • apache portable runtime1.7.0
  • oracle http server12.2.1.3.0
  • oracle http server12.2.1.4.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (apache). Independent of NVD's CPE analysis and usually ahead of it.

  • Apache Software Foundation Apache Portable Runtime (APR)

    • Apache Portable Runtime 1.7.0affected

Package-level exposure

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

EcosystemPackageAffected rangeFix
Alpine:v3.14aprbefore 1.7.0-r11.7.0-r1
Alpine:v3.16aprbefore 1.7.0-r21.7.0-r2
Debian:12aprbefore 1.7.0-71.7.0-7
openSUSE:Tumbleweedaprbefore 1.7.0-4.11.7.0-4.1

Same product

apache: all records

Other highest-scoring records for the same primary product.

  • CVE-2022-28331Apache Portable Runtime (APR): Windows out-of-bounds write in apr_socket_sendv function
    39Monitor
  • CVE-2022-24963Apache Portable Runtime (APR): out-of-bound writes in the apr_encode family of functions
    39Monitor
  • CVE-2012-0840tables/apr_hash.c in the Apache Portable Runtime (APR) library through 1.4.5 computes hash values without restricting the ability to trigger
    33Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2011-0419May 16, 2011 · Stack consumption vulnerability in the fnmatch implementation in apr_fnmatch.c in the Apache Portable Runtime (APR) library before 1.4.3 and
    26Monitor
  • ← EarlierCVE-2017-12613Oct 23, 2017 · When apr_time_exp*() or apr_os_exp_time*() functions are invoked with an invalid month field value in Apache Portable Runtime APR 1.6.2 and
    29Monitor
  • Later →CVE-2023-49582Aug 26, 2024 · Apache Portable Runtime (APR): Unexpected lax shared memory permissions
    22Monitor

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
alpine:apr1.7.0-r1 · Alpine:v3.14Package registry (OSV)
debian:apr1.7.0-7 · Debian:12Package registry (OSV)
opensuse:apr1.7.0-4.1 · openSUSE:TumbleweedPackage 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.

Credits

All researchers

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

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).

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

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

Weakness class (CWE)

CWE-125 · Out-of-bounds Read

CVSS vector

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

ATT&CK techniques

—

Change log

  1. Fix✗ → ✓

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

References

Show all references (15 more)

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

All records