Malicious PDF — malware analysis report

Static analysis result for SHA-256 caa055b52e631012…

MALICIOUS

PDF

73.4 KB Created: 2021-07-04 18:03:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d85e0864570e01ceeceefdeaaafc847e SHA-1: 018e1f7f90bdc78fd9b88f96dd18537d7c303008 SHA-256: caa055b52e631012c17c415058c8a0954b33a89335c4b5f2d6431e57152be245
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users to potentially malicious content. ClamAV and ML classifiers also flagged this PDF as malicious, specifically as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://carpanea.it/wp-content/plugins/super-forms/uploads/php/files/223d5016ab998f59e0948b6ec995957c/vamas.pdf
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/0ppc2kf20khedm8aq260bqn231/pivixezewokadadinefowu.pdf
    • https://akapacha.com/userfiles/file/52217328296.pdf
    • https://kogan-photo.ru/wp-content/plugins/super-forms/uploads/php/files/545899ed122a0e155d64e797054bf9b6/67930256333.pdf
    • http://amadpich.com/userfiles/file/43102241436.pdf
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160878387b118a---bemevelisabap.pdf
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160bd5e4237574---98731367127.pdf
    • https://rugsinc.in/UserFiles/files/58032478152.pdf
    • http://goref.ru/files/file/wibedipapa.pdf
    • https://razvozka24.ru/wp-content/plugins/super-forms/uploads/php/files/b7e9d0d971788e200ac9c92b8790c73a/nujomanejexowanima.pdf
    • http://amon-syotengai.com/userfiles/file/dobawafenipozutumujit.pdf
    • https://tort-art.ru/userfiles/file/14784951990.pdf
    • http://prunay-en-yvelines.fr/ckfinder/userfiles/files/fulimi.pdf
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/2c45ca01aace353ea7b5d4c3e860e9da/40574252806.pdf
    • http://akicgiyim.com/userfiles/file/30425007254.pdf
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/160759defb447a---jinapuf.pdf
    • https://boucherienabli.com/uploads/FCK_files/file/81574743657.pdf
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/267f304e5fd13ea4c62d71f774aa1147/96523421231.pdf
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/7c2a35f91f3666d29f0859594a2c3bc1/sufenig.pdf
    • https://homini.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160794f6c7e66d---tevutulaniged.pdf
    • https://www.tanyadantus.com/wp-content/plugins/super-forms/uploads/php/files/b7d516dc42e55f4962da2338f29c6f30/42233830975.pdf
    • http://snnet.kr/board_pds/fckeditor/2021/06/file/59877942120.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=general+knowledge+books+for+kids+pdf
    • 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_off0000bc55.bin
f13c258a89c3d11d8fe8f022cb12518f1ae1d91a77186156b832ff89a94a12aa
pdf-font-stream PDF embedded font (sfnt) at offset 0xBC55 10932 bytes
font_01_sfnt_off0000d560.bin
343d75e3731aff0cb0aa90106b3a5d66aae50051afa70be353f25e7edffbf065
pdf-font-stream PDF embedded font (sfnt) at offset 0xD560 16512 bytes
font_02_sfnt_off0000fffe.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFFE 16792 bytes