Malicious PDF — malware analysis report

Static analysis result for SHA-256 fba4944c5f27d7c0…

MALICIOUS

PDF

92.0 KB Created: 2021-07-13 19:06:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 362bcd10edb099434ad94f7b3d65731c SHA-1: 29feaa928fed6a76ff614e960b849442e95eac6f SHA-256: fba4944c5f27d7c00c8526cdd2300c12dcf70df8c00d0ce58ed09a18a3d7952e
156 Risk Score

Malware Insights

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

The sample is identified as malicious by ClamAV and an ML classifier, indicating it's likely a phishing or malware distribution lure. Heuristics indicate it functions as a link farm, with numerous URLs pointing to compromised CMS uploads and disposable hosting. The PDF structure itself is also noted as having duplicate object bodies, a common obfuscation technique.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://crewmak.ru/uplcv?utm_term=biotransformation+phase+1+and+2
    • http://charugarware.com/DEVELOPMENT/charu_garware/uploaded/userfiles/file/17702506546.pdf
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/1607516ca00012---11910268517.pdf
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c105471389b---gitow.pdf
    • http://domholidays.com/userfiles/file/pitodi.pdf
    • https://mattress-leader.com/media/81178639162.pdf
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/160bffdc7e61d6---vuwotuje.pdf
    • http://bluekeydigital.com/images/pic/file/5764552602.pdf
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/160adb8d646b3e---gusobobod.pdf
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607dcac66fae0---sesirexibuzomipimataxi.pdf
    • http://nwatchonline.net/userfiles/file/komilanixinujaniken.pdf
    • http://anhuishangbiao.com/upload_fck/file/2021-4-30/20210430171534303719.pdf
    • http://arcdesantmarti.com/biocop/Images/images-editor/file/57362443945.pdf
    • http://www.allatpatikapecs.hu/images/file/76238192557.pdf
    • https://socialacademy.gr/wp-content/plugins/super-forms/uploads/php/files/45ec731085ea22aeea66edbd13f039ef/53439442543.pdf
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ed89624e5d7---tekinumarugigetixatoro.pdf
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/j28bc3cs40657b8lbd7hv8p5o4/98053823829.pdf
    • https://espiber.cl/images/uploadedimages/file/59512317800.pdf
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1607796bda76c3---7011405009.pdf
    • https://vmwarts.com/ecovic/file/68119795019.pdf
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/c864d038e0483042e0969fb3da8f76fa/denalifanetukereze.pdf
    • http://writtenmail.com/upload_images/file/56274210000.pdf
    • http://crmrealty360degree.in/userfiles/file/33008037842.pdf
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b2d1f56b828---37630710798.pdf
    • http://vp-dmsh.ru/admin/ckfinder/userfiles/files/76014954800.pdf
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/5671d239295ddec6e2d7c6ef3994a194/rirevemegegoturazabige.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_off000100ad.bin
681df84d8b07865066386d72bea7083225b90dd8d4cf5a6920ed8d10400e1cbf
pdf-font-stream PDF embedded font (sfnt) at offset 0x100AD 10944 bytes
font_01_sfnt_off000119f4.bin
3f045ec0f57bccb44acacf2d4ca055ba81aa6abd6d7662e14b73701c3f28379f
pdf-font-stream PDF embedded font (sfnt) at offset 0x119F4 18100 bytes
font_02_sfnt_off000148ba.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x148BA 16792 bytes