Malicious PDF — malware analysis report

Static analysis result for SHA-256 8413605052658a0e…

MALICIOUS

PDF

73.8 KB Created: 2021-09-11 00:52:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 51593d0e645aa4f49ea52efeac312dd9 SHA-1: 9c93eeb938ebce26e8164677e11f79ae13f17043 SHA-256: 8413605052658a0e523a989ebb632277f699b6ed522791fb5f0b5a874d839f6a
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to potentially compromised WordPress upload directories or disposable hosting. The embedded URLs suggest an attempt to redirect the user to external, malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://liga-stf.ru/i/upload/files/61067102817.pdf In PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16131b8d5adce3---reroxupavafuxudiwasu.pdfIn PDF document text
    • http://mmprogetti.it/userfiles/files/ratinan.pdfIn PDF document text
    • https://tsegypt.com/file/97123585650.pdfIn PDF document text
    • http://hai-bi.com/uploads/files/202109080745377293.pdfIn PDF document text
    • http://henghuitong.com/jingkelun/userfiles/files/20210908223320.pdfIn PDF document text
    • http://xn----8sbnbd9chja.xn--p1ai/userfiles/file/xafafumomatelel.pdfIn PDF document text
    • http://rebeccafantarchitetto.it/userfiles/files/92882302327.pdfIn PDF document text
    • http://bestbelly.org/content/files/files/nozel.pdfIn PDF document text
    • https://pfollowers.com/ci/userfiles/files/jepupesubulojo.pdfIn PDF document text
    • https://akgoz.zemta.com/uploads/files/wubikilejolebuzotefan.pdfIn PDF document text
    • https://socialacademy.gr/wp-content/plugins/super-forms/uploads/php/files/c4e454cf1d54f2930a8f65c9c9de991d/degigilinuv.pdfIn PDF document text
    • http://sxhk365.com/uploads/file///63282904974.pdfIn PDF document text
    • https://pet-fashion.ro/mm/file/23523521410.pdfIn PDF document text
    • http://krallarintavugu.com/upload/file/figije.pdfIn PDF document text
    • http://bwemfjhjk.friend-match.com/upload/files/65649994450.pdfIn PDF document text
    • http://www.uc-kushiro.net/images/library/File/pemiwivalibadupubonasegir.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bce22057ae---dizejefokos.pdfIn PDF document text
    • https://clap-bas.com/userfiles/file/22947421326.pdfIn PDF document text
    • https://functionalmovement.gr/wp-content/plugins/super-forms/uploads/php/files/827c3b4f8c6f014d4139ccb2ba745dcb/bawinupo.pdfIn PDF document text
    • http://chipublichouse.com/ckfinder/userfiles/files/penowexarirenuxedawatu.pdfIn PDF document text
    • http://xn--12cm8caae5d9a0a0a1dxk6dd.com/user_img/files/9404013980.pdfIn PDF document text
    • http://csc-0898.com/userfiles/file/20210903192142_vgxssh.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=stream+champ+apkPDF 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_off0000be47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE47 10276 bytes
SHA-256: 64969e54fe5bbe86bd818c3257e890dcdf8409752145413d21317d55d07584ea
font_01_sfnt_off0000d574.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD574 17364 bytes
SHA-256: 52d1c00d413f93164654306da490a16a74b28e7c55cfede8f4008f02af478909
font_02_sfnt_off00010217.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10217 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1