CVE-2026-1156939.1CriticalCWE-295

CVE-2026-115693: Custom cacerts or cacertfile do not restrict trust to the pinned CA in hackney

benoitc · hackney

Fixed in 4.9.0 · Affected: benoitc hackney before 4.9.0 · Exploitation: unlikely (under 1%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

0.3%probability of exploitation in the next 30 days

19th percentile

050100

Higher than 19% of scored CVEs

9.1CriticalCVSS 4.0

LowMediumHighCrit.

DescriptionCVE.org

Improper Certificate Validation vulnerability in hackney_ssl in benoitc hackney allows an on-path attacker to impersonate a server pinned to a private certificate authority via a certificate chain that ends in a publicly trusted root. hackney adds {partial_chain, fun hackney_ssl:partial_chain/1} to every verify_peer configuration. The callback returns any certificate in the peer chain whose public key matches a root in the bundled certifi store as the trust anchor, and OTP honours that callback over the configured cacerts. hackney_ssl:merge_ssl_opts/3 kept the callback when the caller replaced the trust store with cacerts or cacertfile in ssl_options, so a connection pinned to a private CA still accepted any chain that carried a publicly trusted root. The hostname check still applies, so the attacker needs a publicly trusted certificate for the pinned hostname. This issue affects hackney: from 1.24.0 before 4.9.0.

Affected products2

From the CVE record. A product or version that is not listed is unknown, not unaffected.

benoitc · hackneyfrom 1.24.0 before 4.9.0
benoitc · hackneyVersions not stated

On the Atlas

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Exploitation: Unlikely (under 1%). EPSS under 1%, or no score yet.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Improper Certificate Validation · Cryptography
Vendor: benoitc
Published: October 2026
Band: Unlikely (under 1%), October 2026

CoverageNo articles yet

No CyberSIXT article names CVE-2026-115693 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.