Malicious PDF — malware analysis report

Static analysis result for SHA-256 4dfb36d8cc8e885c…

MALICIOUS

PDF

96.4 KB Created: 2021-09-13 22:36:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 40d41bfce725f27fdcb4290b6e8061f2 SHA-1: 162cfaf8c0472fb93b967b9edb958eae09f75dcc SHA-256: 4dfb36d8cc8e885c0449da9c76958a5b2a71cad04f3147bb4baa70e72a46364e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by ML classifiers and ClamAV. It contains numerous embedded URLs, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm or phishing lure. The presence of these links indicates an attempt to redirect users to malicious content, likely for credential harvesting or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9888

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://cructi.ru/uplcv?utm_term=without+login+instagram+auto+followers
    • https://khangle.vn/uploads/images/files/35096462397.pdf
    • http://lngpetro.com/userfiles/file/kewifafomuromawerobikol.pdf
    • https://topclassgardening.nl/images/file/91287242966.pdf
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613af4cebfb71---64803060228.pdf
    • http://strahovka66.ru/userfiles/file/lusifolem.pdf
    • http://profstil.az/userfiles/file/rumekusiz.pdf
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/b8746ce6924a9d73d0d53a42e91a5b1d/mapovaf.pdf
    • https://www.medicalbi.com/ckfinder/userfiles/files/bomavewute.pdf
    • http://patrickstaxi.fr/userfiles/file/92546738372.pdf
    • http://www.consorcio.edu.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1613aed362b6a9---28854199311.pdf
    • https://rrr71.ru/upload_picture/90469483576.pdf
    • https://securitydm.net/slicice/file/77727113313.pdf
    • http://9275522-travel.com/userfiles/file/xudisilakixusamor.pdf
    • https://fundoohairstyles.com/hairstyler/images/file/finiv.pdf
    • http://www.celso.org/download/womigiwalamoki.pdf
    • http://atomiccm.com/userfiles/files/55999797526.pdf
    • http://whitedwarf.ru/public/images/ckfinder/files/94407244168.pdf
    • https://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/8be6097efe1116b51bf4bc8144cd576e/98849787593.pdf
    • https://2b3la571ga-70p.com/contents/files/zotawidezixovusat.pdf
    • https://spotiverify.com/ci/userfiles/files/92051360336.pdf
    • http://go-trec.com/wp-content/plugins/super-forms/uploads/php/files/iv4i2gci28a8r4ngqbqsbofkdj/ropukakolebefaga.pdf
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f2a8bdbe2c---95387849053.pdf
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/1612f474536e4e---22175644241.pdf
    • https://serwisnawigacji.pl/userfiles/file/vokuxuxalozarodadoj.pdf
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/a096f4520e3557c16cc172972d2ec100/28790509388.pdf
    • https://ezastupitelstvo.sk/editor_uploads/system/files/gokulezidujinutixas.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_off000112a7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x112A7 16792 bytes
font_01_sfnt_off00012abe.bin
557fb16c8136361d2a6cba1f0fcaa713842328795dcf868978e6b7cc51be3bfa
pdf-font-stream PDF embedded font (sfnt) at offset 0x12ABE 10840 bytes
font_02_sfnt_off000143ae.bin
a3883b0ef447baf1abb944d785cabb542ce616132bcf320ba7a0c948a5effcd3
pdf-font-stream PDF embedded font (sfnt) at offset 0x143AE 18416 bytes