● Low · CVSS 3.7

How to Fix CVE-2026-2708: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

By Sai Kiran Pandrala

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Last verified: 2026-05-25

CVE-2026-2708 is a inconsistent interpretation of http requests ('http request/response smuggling') in Red Hat Red Hat Enterprise Linux 10. Fix it by upgrading to the patched build from the vendor advisory.

⚡ At a glance


Severity	CVSS 3.7 - Low
Actively exploited?	Not currently in the CISA KEV catalog
Affected	See vendor advisory for affected versions
Fixed in	See vendor advisory
Type (CWE)	CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

What is CVE-2026-2708?

CVE-2026-2708 is a inconsistent interpretation of http requests ('http request/response smuggling') flaw in Red Hat Red Hat Enterprise Linux 10. It carries a CVSS base score of 3.7 (low). It is not currently listed in the CISA Known Exploited Vulnerabilities catalog.

From the source record: A request smuggling vulnerability exists in libsoup's HTTP/1 header parsing logic. The soup_message_headers_append_common() function in libsoup/soup-message-headers.c unconditionally appends each header value without validating for duplicate or conflicting Content-Length fields. This allows an attacker to send HTTP requests containing multiple Content-Length headers with differing values.

Why it matters in practice: The blast radius depends on how the affected service is exposed. An internet-facing instance with no compensating controls is the highest-risk configuration.

Am I affected?

You are affected if your installation of Red Hat Enterprise Linux 10 matches a version listed in the Affected row above.


# Debian/Ubuntu
dpkg -s red | grep Version
# RHEL/Rocky
rpm -q red

How to fix CVE-2026-2708

Apply the vendor patch. Target the build named in the Fixed in row above (See vendor advisory). The runnable command set below covers the most common deployment patterns for Red Hat Enterprise Linux 10.

Ubuntu / Debian


sudo apt-get update
sudo apt-get install --only-upgrade red
dpkg -s red | grep Version

RHEL / CentOS / Rocky


sudo dnf upgrade red -y
rpm -q red

After applying the patch

Restart the service or device so the patched binary loads.
Confirm the running version matches the Fixed in row using the verification command below.
Rotate credentials and API keys that the affected service could access if the asset was exposed during the disclosure window.

If you can't patch immediately

Until the patch lands, narrow the attack surface with these runnable controls.

Restrict network exposure

Block public access to the affected service at the perimeter. Allow only trusted source IPs.


# Linux iptables: only allow trusted admin subnet
sudo iptables -A INPUT -p tcp --dport 443 -s 10.10.10.0/24 -j ACCEPT
sudo iptables -A INPUT -p tcp --dport 443 -j DROP
sudo iptables-save | sudo tee /etc/iptables/rules.v4


# Windows firewall: only allow trusted admin subnet on management port
New-NetFirewallRule -DisplayName "Restrict-Mgmt-Allow" -Direction Inbound -Action Allow `
  -RemoteAddress 10.10.10.0/24 -Protocol TCP -LocalPort 443
New-NetFirewallRule -DisplayName "Restrict-Mgmt-Deny"  -Direction Inbound -Action Block `
  -Protocol TCP -LocalPort 443

Mitigations are temporary. Apply the vendor patch as soon as a maintenance window opens.

How to verify the fix worked

Confirm the patched build is the one actually running.


# Debian/Ubuntu
dpkg -s red | grep Version
# RHEL/Rocky
rpm -q red

Expected: a version at or above the patched build named in the vendor advisory.

Also worth doing: pull recent log windows for indicators of compromise listed in the vendor advisory, and re-run an authenticated vulnerability scan with up-to-date signatures.

Frequently asked questions

Is CVE-2026-2708 being exploited in the wild?

As of 2026-05-25, CVE-2026-2708 is not listed in the CISA Known Exploited Vulnerabilities catalog. Watch the catalog and patch on a normal cadence; KEV status can change as exploitation evidence emerges.

What is the CVSS score for CVE-2026-2708?

The CVSS base score is 3.7 (Low).

What version fixes this?

The vendor advisory names the patched build. See the References section.

Will a WAF or IDS rule alone close this?

No. Network filters cut down opportunistic scans but they do not remove the flaw. The vendor patch is the only durable fix.

References

Official vendor advisory: https://access.redhat.com/security/cve/CVE-2026-2708
NVD entry: https://nvd.nist.gov/vuln/detail/CVE-2026-2708
CISA KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog
Additional reference: https://bugzilla.redhat.com/show_bug.cgi?id=2440743
Additional reference: https://gitlab.gnome.org/GNOME/libsoup/-/issues/500
Additional reference: https://gitlab.gnome.org/GNOME/libsoup/-/merge_requests/513

*Assembled from the official vendor advisory, the NVD record, and the CISA KEV listing on 2026-05-25. Always confirm against the vendor advisory before applying changes in production.*