Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc25ceb91b40cb2c…

MALICIOUS

PDF

74.1 KB Created: 2021-09-07 00:51:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 6929472ae218f18a39a747c962e01e1c SHA-1: 413effd9b3dfec67ccebea65e759223bd4181af9 SHA-256: bc25ceb91b40cb2c40b5ed59a534854115c9031d3e584dd82e23fe835def1057
156 Risk Score

Malware Insights

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

The PDF contains numerous external URIs and is identified as a link farm, with many links pointing to compromised CMS upload storage. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the primary attack vector appears to be directing users to malicious external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://krisoc.ru/uplcv?utm_term=jitterbug+smart+2+instruction+manual PDF link annotation
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/16120ef821ad27---32472096090.pdfIn PDF document text
    • http://arunimaflavours.com/userfiles/file/salowugezejun.pdfIn PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbe3fdd0c63---17663088921.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb495988a9---sexakufoxag.pdfIn PDF document text
    • http://edu-family72.ru/content/images/uploads/file/25966359031.pdfIn PDF document text
    • https://blogsma.com/files/nojerew.pdfIn PDF document text
    • http://auksozvynas.lt/userfiles/file/xufizatamefovopuxitutaxi.pdfIn PDF document text
    • https://apoiotelecom.com/imagens/img_fckeditor/file/8057739299.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b86e23e4653---4828232228.pdfIn PDF document text
    • http://bradhelferlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/2280607287.pdfIn PDF document text
    • http://codemessaging.net/ckfinder/userfiles/files/puwefivizomuza.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607033fa67e97---terejajosukujuzegoda.pdfIn PDF document text
    • http://mmprogetti.it/userfiles/files/86469413590.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/de49a0f017bb14eaf28038be5a389f88/benevu.pdfIn PDF document text
    • http://easyhypermarket.com/userfiles/file/setarum.pdfIn PDF document text
    • https://glory-aqua.com/userfiles/file/tupofaxu.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e9a5facece---sijawivoberixopafuz.pdfIn PDF document text
    • http://bydnjl.com/userfiles/files/pipokuvofejakep.pdfIn PDF document text
    • https://appvid.eus/userfiles/files/tatetalewezosakozizuxoben.pdfIn PDF document text
    • http://csc-021.com/userfiles/file/20210809065614_rd9sxa.pdfIn PDF document text
    • http://wpscrm.in/uploaded_files/userfiles/files/nirerusi.pdfIn PDF document text
    • http://makrostal.pl/user_images/file/30193198625.pdfIn PDF document text
    • http://meteosputnik.ru/userfiles/file/kuzebadoja.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608b6651b776b---gupuvuvamulumuvoduwuva.pdfIn PDF document text
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a472ed81243---67350925028.pdfIn PDF document text
    • 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_off0000bd54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD54 10924 bytes
SHA-256: cf2a62298b35d5b08ba52a572a5a53eb9840b1be4607812af48186452a7a4588
font_01_sfnt_off0000d6b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6B8 17264 bytes
SHA-256: ed0c2e25859b6dead96a3c354cec9787415cea58d1af74024014250b9b422c41
font_02_sfnt_off000102d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102D8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1