Legion of the Bouncy Castle Bouncy Castle for Java up to bcpg-fips 2.1.13 High-Level OpenPGP API PGPEncryptedData.verify integrity check

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
7.0	$0-$5k	0.74

Summaryinfo

A vulnerability marked as critical has been reported in Legion of the Bouncy Castle Bouncy Castle for Java, Bouncy Castle for Java LTS and Bouncy Castle for Java FIPS up to 1.85.99/2.73.12/bcpg-fips 1.0.13/bcpg-fips 2.0.14.0/bcpg-fips 2.1.13. This affects the function PGPEncryptedData.verify of the component High-Level OpenPGP API. The manipulation leads to integrity check. This vulnerability is listed as CVE-2026-85515. The attack may be initiated remotely. There is no available exploit. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Legion of the Bouncy Castle Bouncy Castle for Java, Bouncy Castle for Java LTS and Bouncy Castle for Java FIPS up to 1.85.99/2.73.12/bcpg-fips 1.0.13/bcpg-fips 2.0.14.0/bcpg-fips 2.1.13. It has been rated as critical. This issue affects the function PGPEncryptedData.verify of the component High-Level OpenPGP API. The manipulation with an unknown input leads to a integrity check vulnerability. Using CWE to declare the problem leads to CWE-354. The product does not validate or incorrectly validates the integrity check values or "checksums" of a message. This may prevent it from detecting if the data has been modified or corrupted in transmission. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

In Bouncy Castle for Java before 1.86, a truncated OpenPGP encrypted message was accepted with no error reported, and on the SEIPD version 1 path with no integrity check performed at all. RFC 9580 sec. 13.7 permits an implementation to release the cleartext of the fully authenticated chunks when streaming but requires it to indicate a clear error as soon as the truncation is detected, and to report suspect integrity when it discovers malleable ciphertext. The truncation was detected and then discarded: when a message is truncated but the length field of the enclosing packet is left unchanged, BCPGInputStream.PartialInputStream raises an EOFException for the missing ciphertext, and BCPGInputStream.nextPacketTag() reports an EOFException as a clean end of message, so the packet stream above it stopped as though no packets remained. On the AEAD path (SEIPD version 2 and the version 5 AEAD packet), when the literal data packet ended on an AEAD chunk boundary and the consumer read in increments smaller than one chunk, the look-ahead for the packet after the literal triggered the truncated chunk read, so BcAEADUtil and JceAEADUtil never reached the trailing message tag of sec. 5.13.2 that authenticates the total plaintext length; the caller received the plaintext of the fully authenticated chunks, every packet following the literal was silently dropped, and no exception was raised, so a signed and encrypted message read back as a well-formed unsigned one. Every byte released on that path remained individually authenticated, making this a missing truncation error rather than a forgery, and it is a residual of CVE-2026-12817, which closed the same outcome for an attacker who corrects the outer packet length. On the SEIPD version 1 path the consequence was more serious: IntegrityProtectedInputStream verifies the modification detection code from close(), and reached close() only by closing itself when a read of it returned -1, which a truncated message never produces, so PGPEncryptedData.verify() never ran and the recipient was handed CFB-decrypted plaintext on which no integrity check of any kind had been performed. Measured on a message truncated into that shape, 136 distinct single-byte modifications of the ciphertext produced accepted, altered plaintext with no exception raised. Reachability is a property of the message rather than of attacker-supplied input: the AEAD shape held for 3 of 131 consecutive payload lengths measured, and the SEIPD version 1 shape for one payload length in sixteen, at a truncation offset that did not move with the payload length. The low-level API is unaffected, a caller that invokes PGPEncryptedData.verify() directly getting the check regardless, as are consumers reading in increments of a whole AEAD chunk or more. The AEAD decryption streams now re-throw such an EOFException as a plain IOException, which nextPacketTag() does not launder; OpenPGPMessageInputStream.close() now closes its layer's integrity-protected stream itself rather than relying on that stream having seen the end of its data; and IntegrityProtectedInputStream.close() was made idempotent, as java.io.Closeable requires, which that depends on, since the stream is genuinely closed twice on the ordinary path and PGPEncryptedData.verify() consumes the digest state behind it and cannot be run a second time. This issue also affects Bouncy Castle for Java LTS before 2.73.13, on the AEAD route only, as that edition does not ship the high-level OpenPGP API the SEIPDv1 route runs through. It also affects Bouncy Castle for Java FIPS (BC-FJA) before bcpg-fips 1.0.14 (1.0.X series), 2.0.14.1 (2.0.X series) and 2.1.14 (2.1.X series), on the AEAD route only, as those editions do not ship the high-level OpenPGP API.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-85515 since 09/04/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are known, but no exploit is available.

Upgrading to version 1.86, 2.73.13, bcpg-fips 1.0.14, bcpg-fips 2.0.14.1 or bcpg-fips 2.1.14 eliminates this vulnerability.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

• Programming Language Software

Vendor

• Legion of the Bouncy Castle

Name

• Bouncy Castle for Java
• Bouncy Castle for Java FIPS
• Bouncy Castle for Java LTS

Version

• 1.85.0
• 1.85.1
• 1.85.2
• 1.85.3
• 1.85.4
• 1.85.5
• 1.85.6
• 1.85.7
• 1.85.8
• 1.85.9
• 1.85.10
• 1.85.11
• 1.85.12
• 1.85.13
• 1.85.14
• 1.85.15
• 1.85.16
• 1.85.17
• 1.85.18
• 1.85.19
• 1.85.20
• 1.85.21
• 1.85.22
• 1.85.23
• 1.85.24
• 1.85.25
• 1.85.26
• 1.85.27
• 1.85.28
• 1.85.29
• 1.85.30
• 1.85.31
• 1.85.32
• 1.85.33
• 1.85.34
• 1.85.35
• 1.85.36
• 1.85.37
• 1.85.38
• 1.85.39
• 1.85.40
• 1.85.41
• 1.85.42
• 1.85.43
• 1.85.44
• 1.85.45
• 1.85.46
• 1.85.47
• 1.85.48
• 1.85.49
• 1.85.50
• 1.85.51
• 1.85.52
• 1.85.53
• 1.85.54
• 1.85.55
• 1.85.56
• 1.85.57
• 1.85.58
• 1.85.59
• 1.85.60
• 1.85.61
• 1.85.62
• 1.85.63
• 1.85.64
• 1.85.65
• 1.85.66
• 1.85.67
• 1.85.68
• 1.85.69
• 1.85.70
• 1.85.71
• 1.85.72
• 1.85.73
• 1.85.74
• 1.85.75
• 1.85.76
• 1.85.77
• 1.85.78
• 1.85.79
• 1.85.80
• 1.85.81
• 1.85.82
• 1.85.83
• 1.85.84
• 1.85.85
• 1.85.86
• 1.85.87
• 1.85.88
• 1.85.89
• 1.85.90
• 1.85.91
• 1.85.92
• 1.85.93
• 1.85.94
• 1.85.95
• 1.85.96
• 1.85.97
• 1.85.98
• 1.85.99
• 2.73.0
• 2.73.1
• 2.73.2
• 2.73.3
• 2.73.4
• 2.73.5
• 2.73.6
• 2.73.7
• 2.73.8
• 2.73.9
• 2.73.10
• 2.73.11
• 2.73.12
• bcpg-fips 1.0.0
• bcpg-fips 1.0.1
• bcpg-fips 1.0.2
• bcpg-fips 1.0.3
• bcpg-fips 1.0.4
• bcpg-fips 1.0.5
• bcpg-fips 1.0.6
• bcpg-fips 1.0.7
• bcpg-fips 1.0.8
• bcpg-fips 1.0.9
• bcpg-fips 1.0.10
• bcpg-fips 1.0.11
• bcpg-fips 1.0.12
• bcpg-fips 1.0.13
• bcpg-fips 2.0.0
• bcpg-fips 2.0.1
• bcpg-fips 2.0.2
• bcpg-fips 2.0.3
• bcpg-fips 2.0.4
• bcpg-fips 2.0.5
• bcpg-fips 2.0.6
• bcpg-fips 2.0.7
• bcpg-fips 2.0.8
• bcpg-fips 2.0.9
• bcpg-fips 2.0.10
• bcpg-fips 2.0.11
• bcpg-fips 2.0.12
• bcpg-fips 2.0.13
• bcpg-fips 2.0.14.0
• bcpg-fips 2.1.0
• bcpg-fips 2.1.1
• bcpg-fips 2.1.2
• bcpg-fips 2.1.3
• bcpg-fips 2.1.4
• bcpg-fips 2.1.5
• bcpg-fips 2.1.6
• bcpg-fips 2.1.7
• bcpg-fips 2.1.8
• bcpg-fips 2.1.9
• bcpg-fips 2.1.10
• bcpg-fips 2.1.11
• bcpg-fips 2.1.12
• bcpg-fips 2.1.13

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.0

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Integrity check
CWE: CWE-354 / CWE-345
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Bouncy Castle for Java/Bouncy Castle for Java LTS/Bouncy Castle for Java FIPS 1.86/2.73.13/bcpg-fips 1.0.14/bcpg-fips 2.0.14.1/bcpg-fips 2.1.14

Timelineinfo

09/04/2026 CVE reserved
10/03/2026 +29 days Advisory disclosed
10/03/2026 +0 days VulDB entry created
10/03/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-85515 (🔒)
GCVE (CVE): GCVE-0-2026-85515
GCVE (VulDB): GCVE-100-413333

Entryinfo

Created: 10/03/2026 10:51
Changes: 10/03/2026 10:51 (70)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Discussion

Want to stay up to date on a daily basis?

Enable the mail alert feature now!