Malicious PDF — malware analysis report

Static analysis result for SHA-256 3bfb57dfc404da9a…

MALICIOUS

PDF

82.5 KB Created: 2021-09-10 18:21:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5d607c6e2ef1deea0ec96fcb0fe58723 SHA-1: 0d28279c2ae17c7525e36f01dd1beea25d333e8d SHA-256: 3bfb57dfc404da9a46d91ad92303928f475f237f23533a9ef26eef26881b6ac5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external links, many pointing to compromised CMS upload directories, suggesting a phishing or malware distribution scheme. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this, indicating the PDF acts as a link farm to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://garglob.ru/uplcv?utm_term=henry+stickmin+collection+apk+download
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139ae3cb6a15---34533989986.pdf
    • http://mwbright.com/upload_fck/file/2021-9-10/20210910073507218408.pdf
    • http://schokozentrale.de/idata/digitojifer.pdf
    • https://fwstc.in/userfiles/file/42574562882.pdf
    • http://ivankotov.ru/img/lib/file/kisovijexufuwupepevi.pdf
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/4792bf435ea8b814cdea7710500d3802/13006046558.pdf
    • https://guijek.com/userfiles/file/43508218159.pdf
    • http://hrudolf.com/userfiles/gaxiwubadinowo.pdf
    • http://aven.su/userfiles/file/bukajuteri.pdf
    • http://jorkurojus.com/userfiles/file/marexojokuruwalofimara.pdf
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/1612fef5698309---nerodewake.pdf
    • https://network-italia.it/file/27736089212.pdf
    • https://klubkanine.com/home/klub/public_html/ckfinder/userfiles/files/86915427586.pdf
    • https://istanajp.com/contents/files/ranalom.pdf
    • https://noelex22.org/userfiles/file/40513311407.pdf
    • http://afslab.asia/upload/files/vilipasorukavadoluxipag.pdf
    • http://goodfortune.hk/UpLoadFile/file///72488947256.pdf
    • https://tcremich.lu/files/files/73245401891.pdf
    • http://toitureetfacade.fr/data/Files/62151468589.pdf
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130048813232---72808482005.pdf
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/16133037be10ae---8316947284.pdf
    • http://jaatkinson.com/userimages/93938560221.pdf
    • https://manenshop.com/upload/files/kekipalasugawulaxaniw.pdf
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136c6c20090f---fanebub.pdf
    • http://geosond.pl/userfiles/file/bavejudowa.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_off0000d549.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD549 16792 bytes
font_01_sfnt_off0000ed60.bin
94b6fe6817a3e3353b96a9860b20610af6a76f8294bcc5971abbea721eb9c2f4
pdf-font-stream PDF embedded font (sfnt) at offset 0xED60 10956 bytes
font_02_sfnt_off000106d2.bin
b374d9c05eb556026acc25ef4150d1126ff59e7e24db09aec9ffff26a5a371e7
pdf-font-stream PDF embedded font (sfnt) at offset 0x106D2 20328 bytes