Malicious PDF — malware analysis report

Static analysis result for SHA-256 50a8a0251062b557…

MALICIOUS

PDF

89.1 KB Created: 2021-09-02 02:45:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 323f16dab1e9ac2de7ec7fd2682222c5 SHA-1: 6144f1ea5dcb57a99b9dcadbb95c0d9a504561ea SHA-256: 50a8a0251062b55787298755e76e5ae661bc73001718afcc0be393a8f101cabf
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 websites hosted on compromised CMS platforms or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' directly support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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 http://sibstroiexp.ru/userfiles/file/75158524947.pdf
    • http://agriturismofattorialucciano.com/ckfinder/userfiles/files/41947308050.pdf
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607accb6eb3ff---16090667144.pdf
    • https://506hlapeta.com/files/file/bugotinekusozevebemag.pdf
    • http://hongshengfish.com/uploadfiles/2021062300250779907.pdf
    • http://primaria-ciocirlia.ro/media/file/popazefaxegatimow.pdf
    • http://www.allatpatikapecs.hu/images/file/68862956102.pdf
    • http://urparitet.ru/admin/ckfinder/userfiles/files/96196210819.pdf
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160856d843b0fb---xakeragudidumulagodeve.pdf
    • http://slesnick.net/userfiles/files/84967294369.pdf
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081ee4730e60---terexuba.pdf
    • http://www.sempresaude.net/wp-content/plugins/formcraft/file-upload/server/content/files/16096044de3fee---71043719752.pdf
    • http://mesahighclassof64.com/clients/874441/File/zopudof.pdf
    • http://sensi-leszno.pl/userfiles/file/bobagoxebujijegujeru.pdf
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/qkqj739rdj563kjhq5in3p4hfo/11953044511.pdf
    • http://poltinka.ru/userfiles/file/kutinazexu.pdf
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1609042f79183e---26538291150.pdf
    • http://lindseyderence.com/userfiles/files/31880278043.pdf
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/v31g55ko5av7v1mnbo8vrsoj53/raduvisodime.pdf
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160c5c378db53a---kobasu.pdf
    • https://webtechnocrats.com/upload/file/32779932284.pdf
    • http://446888.top/userfiles/file/66410334808.pdf
    • http://lyzjkgm.com/d/files/rawalezuxezaxubapo.pdf
    • https://afd.me.uk/wp-content/plugins/super-forms/uploads/php/files/mkpllue3ragcm486j57hunfu16/xivetijavodatalema.pdf
    • https://lostsoulsmemorialnj.org/wp-content/plugins/super-forms/uploads/php/files/63a330317c1f874d0f78275f243ad46a/68643308405.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=ice+breaking+introduce+yourself
    • 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_off0000f4e2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF4E2 16792 bytes
font_01_sfnt_off00010cf4.bin
fd1972681c4e8a0adebf8e3502d12559c6be54648ebeadffced376f9f371ea53
pdf-font-stream PDF embedded font (sfnt) at offset 0x10CF4 18188 bytes
font_02_sfnt_off00013bde.bin
2f982eb25e927f0780114e99e1b16626451d49e482dffcb34b5818b240a8383f
pdf-font-stream PDF embedded font (sfnt) at offset 0x13BDE 11048 bytes