Malicious PDF — malware analysis report

Static analysis result for SHA-256 b77db9b012595f7a…

MALICIOUS

PDF

103.2 KB Created: 2021-07-13 20:54:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: abcea48be61e11d92d86cd457950bbbe SHA-1: 87fcc908d5901ce46444fc951577df76159d7092 SHA-256: b77db9b012595f7ae12a6d5ca4b4ad0477d31ab4f9c2311bc0ba25bfbfba41fe
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links pointing to compromised WordPress sites, indicating a link farm designed to host or distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. The document body is heavily obfuscated and does not provide direct clues, but the heuristic findings and numerous external URLs are strong indicators of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/e7fac11365ca240390676e6d69befe25/82082792377.pdf
    • http://andlupa.com/userfiles/file/22792132474.pdf
    • http://otvorene-srdce.sk/userfiles/file/devapedexununatajivuxegax.pdf
    • http://soldearenales.com/galeria/files/pesoxe.pdf
    • http://projectbudapest.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1608816ade07a6---fowoxulubikaka.pdf
    • http://tourbusan.net/FileData/ckfinder/files/20210713_B843600E0E9DD11A.pdf
    • http://theopenhouseclub.com/wp-content/plugins/super-forms/uploads/php/files/b11db96260a2db76f841a13ce6eeed63/segivukegakaputibuxilit.pdf
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/160afc91bcee89---wukumofigavewawas.pdf
    • http://ohsongpharm.com/ckfinder/userfiles/files/lojudemosenodikekif.pdf
    • http://alexlunacoach.com/img/editor/file/dunisunejiwe.pdf
    • http://kajsanordstrom.com/userfiles/files/21982523070.pdf
    • http://digifast.cz/userfiles/puvumonoletenowaxonu.pdf
    • http://martom24.pl/martom/userfiles/file/nutegebakimemadijivixele.pdf
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/5814qb3o7q9l9u7no41cusqa42/24881710626.pdf
    • https://carstenrath.com/wp-content/plugins/super-forms/uploads/php/files/30odsdrdf77881pmrk0olve5ju/89501520218.pdf
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/6c328d53f3a1b9bec47a1852903fa379/13546431761.pdf
    • https://alsterparkett.de/wp-content/plugins/super-forms/uploads/php/files/nf294utn9vd9rii2pkgeuppgst/23730587542.pdf
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a784022d88f---99222692975.pdf
    • http://innotec-industrie.be/userfiles/file/besona.pdf
    • http://amoy-art.com/Upload/file/97942738566.pdf
    • http://ewinghighclassof1963.com/clients/e/e4/e4cb61fc1babc639533983e887b7272d/File/91736136977.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=12+military+time
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001311a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1311A 16792 bytes
font_01_sfnt_off0001492c.bin
e68ec8a62c29993ea1f81fb28ef89bac8e0c157f0a1bcbea40e530f95c61c3a5
pdf-font-stream PDF embedded font (sfnt) at offset 0x1492C 19076 bytes
font_02_sfnt_off000179d7.bin
3d77b7eaf0fea1b5e84883249d96b6011b04c294cf0c479f314769ac0f0d31f7
pdf-font-stream PDF embedded font (sfnt) at offset 0x179D7 10068 bytes