Malicious PDF — malware analysis report

Static analysis result for SHA-256 88bdb8d781a8f3d0…

MALICIOUS

PDF

94.3 KB Created: 2021-07-30 22:07:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 50993f9904486875765c65f590025074 SHA-1: 9d9108e1fda96e2a3c888f51d9c7ef7caf271340 SHA-256: 88bdb8d781a8f3d09881ceba666bec4a80ff9e1624a5b6077dd29f7375f3bffe
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous embedded URLs pointing to various domains, many of which appear to be compromised WordPress sites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a non-clustered link farm on disposable hosting, suggesting an attempt to redirect users to malicious content. The ClamAV detection and ML classifier further support its malicious nature, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://infrive.ru/uplcv?utm_term=d%C3%A9nombrement+exercices+corrig%C3%A9s+mpsi+pdf
    • https://muahohangnhat.com/app/webroot/uploads/files/worizoputef.pdf
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160822e6cae753---jonim.pdf
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/4453f5f9fa31dd4ceaf79e5eea16cd67/48373683163.pdf
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/0e17c74ae33d004660e7c33579135696/47727195058.pdf
    • http://santamariamikado.com/uploads/files/80126577454.pdf
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160bd57a3bcf32---89530697330.pdf
    • https://alexandrapanayotou.com/web/images/static/file/42021104958.pdf
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608307d24c007---72162578576.pdf
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/011ebaeb3d424466a2d90eec1052c68c/33868048505.pdf
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16077213dbfa45---wefobujin.pdf
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c3a044f55b---6633869477.pdf
    • https://www.displaysdirectaustralia.com.au/application/third_party/ckfinder/userfiles/files/55251916145.pdf
    • https://singaporenotarypublic.com/wp-content/plugins/super-forms/uploads/php/files/e7a5d307fa0bac4b002a5060048769ed/ralowewotozezofofapenedut.pdf
    • https://rockyshairsalon.com/wp-content/plugins/super-forms/uploads/php/files/l0mh71tsvdiqc1jbucndi1s4mi/fabinonagevanedodedeme.pdf
    • https://motionslam.com/wp-content/plugins/super-forms/uploads/php/files/fe40eadf49df48e081635325ad885e1a/60237117736.pdf
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/7467e2af594c5d585aa0dfe60f0bc0be/64473642252.pdf
    • http://www.greenfield-sustainability.com/images/files/manifejuxutamenojem.pdf
    • http://archimax.ch/dynamic-images/cms/file/43947401145.pdf
    • http://gayaarchi.com/userfiles/file/20210730085300.pdf
    • https://thealloywheelcentre.co.uk/wp-content/plugins/super-forms/uploads/php/files/fc573c0a0eea445d2a22b333ed1a2972/1526435522.pdf
    • https://www.cpro.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607bdf62cb7e9---lemokaponanotegawavekum.pdf
    • https://botroul.be/uploads/wukepebuzusegobazofa.pdf
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/cb63ef2d8dc4c969652554938efeef75/xixuwiso.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_off0001064d.bin
7beab8efb390811c5485319460d72ff97452ed98f9cd5adde59172a431ed1543
pdf-font-stream PDF embedded font (sfnt) at offset 0x1064D 11152 bytes
font_01_sfnt_off00011fa6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11FA6 16792 bytes
font_02_sfnt_off000137b8.bin
e986867832318701b7a4f795ffd8aa333c4a1b1a5b01be1f1073b57ba5de4820
pdf-font-stream PDF embedded font (sfnt) at offset 0x137B8 19396 bytes