Malicious PDF — malware analysis report

Static analysis result for SHA-256 9127c1ed178fae02…

MALICIOUS

PDF

11.8 KB
MD5: f680d37d010bc7a74f2b1a02821a3f30 SHA-1: eaafbb5c6bb4ef4645647e74b0cd9cdc37175d01 SHA-256: 9127c1ed178fae025ac58f9bf6cc90cbf2c0dc83bcc71f2951be7a16288d1659
186 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link

The PDF file contains embedded JavaScript that leverages the CVE-2007-5659 vulnerability, specifically using the Collab.collectEmailInfo method. This JavaScript acts as a stager, indicated by the heuristic 'PDF_ANNOT_SUBJECT_CALLEE_HEX_STAGER' and the presence of deobfuscated JavaScript files. The primary function of this stager is to download and execute a secondary payload, as suggested by the ClamAV detection 'Pdf.Exploit.Agent-36063'. No specific family could be identified, but the exploit and stager mechanism are clear.

Heuristics 7

  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
  • ClamAV: Pdf.Exploit.Agent-36063 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36063
  • Annotation subject callee-key hex JavaScript stager high PDF_ANNOT_SUBJECT_CALLEE_HEX_STAGER
    PDF JavaScript uses syncAnnotScan()/getAnnots() to read an indirect annotation /Subject stream, percent-decodes it through marker replacement, then uses a callee.toString()-derived key to decode and eval the final exploit stage.
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • syncAnnotScan annotation-staging primitive low PDF_FOXIT_SYNCANNOTSCAN
    PDF JavaScript calls syncAnnotScan() — a no-op annotation-enumeration primitive used by exploit-kit JavaScript to stage payload reads from annotation /Subject fields before eval(). Not a vulnerable sink itself; rarely seen in legitimate PDFs. (matched in decompressed stream)
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
eb39e2de4dbbc100de6d3e30aa43ff78fa075618862ba1ebba5151ea3a3b848d
pdf-javascript-stream PDF /JS object 7 at offset 0x19D 273 bytes
annotation_subject_callee_hex_stage_000.js
2c389db3f166effa4ffe269430eb39bd80dc901badb273f9f852d68075b18629
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 4983 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
legacy_pdfkit_stage_001.js
a8725ab36e6dda0dd8a9d43b11bc03488ebaa39b50fff20d6aa61d8a91d39f53
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 11944 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
deobfuscated.js
9869924d6280905cb35dd1e9cd37506162d940d161f043eee2ffba5e96153a72
deobfuscated-js PDF JavaScript deobfuscation pass 66678 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).