Skip to content
Noroxi
NVD / CVE Program· CNA wolfSSL

CVE-2026-6678: Integer underflow in wc_PKCS7_DecryptOri handling crafted Other Recipient Info

Noroxi assessment

Priority: Monitor (action score 4/100)

  • 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: 0.33% (FIRST EPSS).
  • Someone with local access to the system can trigger it. A low-privileged account is enough. Special conditions such as timing or configuration are required.
  • Fixed version: wolfssl (Debian:12) 5.5.4-2+deb12u3; wolfssl (Debian:13) 5.7.2-0.1+deb13u2.

Low priority for now. Upgrade to wolfssl (Debian:12) 5.5.4-2+deb12u3; wolfssl (Debian:13) 5.7.2-0.1+deb13u2 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

Integer underflow in wc_PKCS7_DecryptOri when handling crafted Other Recipient Info, leading to incorrect length handling during decryption.

LowCVSS 1.0 · v4.0—No exploit Fix available
Published
Jun 25, 2026
Updated
Jul 1, 2026
EPSS
0.3% · 26th percentile

Report tools

JSON

Action score

4

Monitor

Low priority for now.

CVSS
4 / 40 · 1.0 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.3%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · wolfSSL
1.0
NVD has not scored this yet; the score shown is the CNA’s.

CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/U:Clear

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

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-2026-6678

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 wolfssl 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
wolfsslwolfssl

Check your server's TLS configuration

The wolfSSL version can't be seen from outside; the free SSL checker tests your certificate, enabled TLS versions and weak ciphers. Confirm the version on your server with the package manager.

Run the SSL check

Affected versions

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

  • wolfssl wolfssl3.15.5 and later · before 5.9.2

Versions reported by the vendor

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

  • wolfSSL wolfSSL

    • 3.15.5 and later · up to and including 5.9.1affected · semver

Package-level exposure

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

EcosystemPackageAffected rangeFix
Debian:12wolfsslbefore 5.5.4-2+deb12u35.5.4-2+deb12u3
Debian:13wolfsslbefore 5.7.2-0.1+deb13u25.7.2-0.1+deb13u2

Same product

wolfssl: all records

Other highest-scoring records for the same primary product.

  • CVE-2017-13099wolfSSL Bleichenbacher/ROBOT
    60This week
  • CVE-2019-11873wolfSSL 4.0.0 has a Buffer Overflow in DoPreSharedKeys in tls13.c when a current identity size is greater than a client identity size.
    42Plan
  • CVE-2017-2800A specially crafted x509 certificate can cause a single out of bounds byte overwrite in wolfSSL through 3.10.2 resulting in potential certif
    42Plan

Published before and after this one in the same product

  • ← EarlierCVE-2026-6412Jun 25, 2026 · Continued acceptance of SHA-1/MD5 digests in certificate processing
    9Monitor
  • ← EarlierCVE-2026-6450Jun 25, 2026 · CRL critical extension bypass in ParseCRL_Extensions
    4Monitor
  • Later →CVE-2026-6679Jun 25, 2026 · DTLS 1.3 ACK serialization heap buffer overflow via integer truncation
    35Monitor

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:wolfssl5.5.4-2+deb12u3 · Debian:12Package 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.

No history yet (it accumulates with the daily EPSS job).

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.

  • CVE-2026-518876 days apartInteger underflow in X.509 SAN parsing in wolfSSL
    9Monitor
  • CVE-2026-577877 days apartInteger underflow leads to out-of-bounds access in sniffer ChaCha decrypt path.
    8Monitor
  • CVE-2026-100598 days apartInteger underflow leads to out-of-bounds access in sniffer AES-GCM/CCM/ARIA-GCM decrypt path
    8Monitor
  • CVE-2025-11931216 days apartInteger Underflow Leads to Out-of-Bounds Access in XChaCha20-Poly1305 Decrypt
    8Monitor

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.
  • Special conditions such as timing or configuration are required.

If successful

Confidentiality
Integrity
Availability
Attack vector
Local
Attack complexity
High
Privileges required
Low
User interaction
P
Scope
X

Weakness class (CWE)

CWE-191 · Integer Underflow (Wrap or Wraparound)

CVSS vector

CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Clear

nvd-secondary

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 (2 more)

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

All records