Malicious PDF — malware analysis report

Static analysis result for SHA-256 6251da65ed71b8e6…

MALICIOUS

PDF

95.5 KB Created: 2021-07-08 03:30:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 4906a42a5a1445d7c44b4e30ae47fa7a SHA-1: 964750240b8db2e221586cc67879dcd1a3ca39a5 SHA-256: 6251da65ed71b8e655fe53577687eefc7c69ea426c3632085c337bf5117c3c25
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of links, many pointing to compromised CMS upload directories or disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

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://citytrafik.nu/images/file/domukudavafixiwujakiduzu.pdf In PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e1ea0eaf8f6---17656511392.pdfIn PDF document text
    • https://inchiriereelicopterromania.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608e18aa33faf---sefawov.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/968ef647003ea161b20a40fce960c2a3/wizoraximefilutodib.pdfIn PDF document text
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/74afceed9d90af16bef8b2dbc976fa6c/zokoju.pdfIn PDF document text
    • https://www.carrentchiengmai.com/files/22790776057.pdfIn PDF document text
    • http://swaminarayangm.org/userfiles/file/21572507275.pdfIn PDF document text
    • http://zhengfutz.com/v15/Upload/file/2021611955501470.pdfIn PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/93mvi4g9vvl6lnhjivpr277v66/90861390111.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e2db32cb4b---25785656783.pdfIn PDF document text
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/160e3d16a64e6b---77347761586.pdfIn PDF document text
    • http://fashioncenterpoint.com/wp-content/plugins/super-forms/uploads/php/files/70d1fd64ab5d390837ca099cbd221dbe/likaporadimuf.pdfIn PDF document text
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1b3839a689---56884857564.pdfIn PDF document text
    • http://colafranceschi.it/userfiles/files/paguzi.pdfIn PDF document text
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/b9872069c3228bac1a4394e30006b9e9/78062098500.pdfIn PDF document text
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/38dc96bb82fb327574572acf26239d80/rufogumetuxigurevi.pdfIn PDF document text
    • https://www.djluk.co.uk/wp-content/plugins/super-forms/uploads/php/files/32l8p1c9rc3pth8j72ff9ur9eu/zejovasazefa.pdfIn PDF document text
    • https://catbasailing.com/upload/fck/file/rufimamuvigaki.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089f8025bffb---47224183139.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b29cffbc794---nojawa.pdfIn PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/6kshrmevvdf7dmnclncr5us1d4/5987122074.pdfIn PDF document text
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/8c74b3282cbcd2597623268022ad3c13/juvejopapeka.pdfIn PDF document text
    • https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/581b64d09ad8cb617ba97f176b33a860/demojolu.pdfIn PDF document text
    • https://vayamcs.com/content_files/files/26280143447.pdfIn PDF document text
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160737cf56b2f1---bibebuvirowex.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=another+word+for+theocracyPDF 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_off00010f28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F28 19040 bytes
SHA-256: 02fb14855e27c7382238f0028aa3c149853e74678f2f1b1f43b9adea74502366
font_01_sfnt_off00013f61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F61 10448 bytes
SHA-256: ff02206087e9276bf75d09e064e26510e5e813ccc6de2e80393799178996aa85
font_02_sfnt_off00015725.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15725 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1