Malicious PDF — malware analysis report

Static analysis result for SHA-256 13bfc1a9d16eca23…

MALICIOUS

PDF

87.3 KB Created: 2021-06-29 00:27:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 6a880a308155aee900c9d6075627708e SHA-1: f8ced8ac677927f806f27c7dca56bef5779657a2 SHA-256: 13bfc1a9d16eca23381640af1e39313dc7e56dab3a108ba3cdb1c9b64b077eeb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with numerous URLs pointing to compromised WordPress sites. While no scripts were explicitly extracted, the PDF structure and the nature of the URLs suggest it is designed to lure users to malicious content, potentially for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/06nbuv1bc9muqr0nujjhptsrc2/34440443249.pdf In PDF document text
    • https://xn--i1aam8cb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/5375dab55f8acabd8e5599de7ef23d71/lomalerugobuzowupa.pdfIn PDF document text
    • http://cricalliance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a0f2c80cf8---55284713392.pdfIn PDF document text
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/fd424c4ff31dfaab591306026e2343d3/76296625009.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609f52900effb---tituvizofajazunanirid.pdfIn PDF document text
    • http://alianzablue.com/aym_image/files/88315712355.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b188409a2f3---gabutos.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/6093e3a5c5bfe288c3999d61feb3ee28/xowefavivaj.pdfIn PDF document text
    • https://fedico.ca/upload/editor/file/zerisu.pdfIn PDF document text
    • https://rebel-guitars.com/wp-content/plugins/super-forms/uploads/php/files/29ae575e795e7213f198902de120fca3/dijeguginowegexi.pdfIn PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160a3d2b643598---23273732750.pdfIn PDF document text
    • https://classicandcamper.co.uk/wp-content/plugins/super-forms/uploads/php/files/teere87a3su6dn2grp317939no/85845647312.pdfIn PDF document text
    • https://southtours.com/wp-content/plugins/super-forms/uploads/php/files/acog57r1m5thgki0cnc72ghb7o/67421623450.pdfIn PDF document text
    • https://www.drmarlenebothma.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160cd2e7fc2dda---kovas.pdfIn PDF document text
    • http://www.euro-fly.eu/userfiles/files/60586279142.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093f3848bcf9---kusonifatomezopu.pdfIn PDF document text
    • http://www.monts.sk/upload_images/file/29523440071.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160bae58e8952a---53258895504.pdfIn PDF document text
    • http://amuseonline.com/absite/userfiles/file/gasupanadivoso.pdfIn PDF document text
    • https://xn--80aaaglcftt5alesfkk7f.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/cb3e9b49f484873334539f062c5216b0/xibujigujogibopinuvonugos.pdfIn PDF document text
    • http://locthanhwindow.com/img_duhoc/files/zizomixibafuxanozog.pdfIn PDF document text
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/32571a50280e2a799bab009920341b09/tegugimolujij.pdfIn PDF document text
    • https://www.propertyfilevault.com/wp-content/plugins/super-forms/uploads/php/files/d9eb8acab201811e37f143d56659a6e0/44788529149.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=baptism+of+the+lord+bible+versePDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f2c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2C9 16868 bytes
SHA-256: 4c1d8dac8bd53688add25cb31bdecb28a24ed2800797885dfda57e2439711392
font_01_sfnt_off00011e8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E8A 10920 bytes
SHA-256: 6ab0eefadb6d38e9958731b80c07d208a9df4b6feb07a28d4fecdc4b99b3c448
font_02_sfnt_off000137ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137AE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1