Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f9679f5ca1d7243…

MALICIOUS

PDF

82.2 KB Created: 2021-07-07 06:05:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 02746df03d7e594ba39c223f820b4ff5 SHA-1: 0f78b13e44a9a98aa3043ca244b9a0a0e94f6fb8 SHA-256: 5f9679f5ca1d7243f5679096ce536c5f98a952f308dc190e285f1cd7760365d4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF contains a link farm pointing to multiple compromised WordPress sites, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were extracted, the presence of numerous external links and the heuristic firings related to link farms and compromised CMS uploads are sufficient to infer a malicious attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://oiweld.com/wp-content/plugins/super-forms/uploads/php/files/b89f23a707865476f90600796fbd55a9/nekeded.pdf
    • http://tantex.org/tantex/tantexuserfiles/file/gamivomeraluzomupa.pdf
    • http://onlineexpert.in/userfiles/file/dimikikev.pdf
    • http://hotararicedo.ro/files/files/69133941688.pdf
    • https://candbco.com/ckfinder/userfiles/files/90237920227.pdf
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/ced9a6f7beaabe925316c59b02181301/50960311310.pdf
    • https://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080d1f75e1a3---41201730814.pdf
    • http://khochailo.com/upload/ck/files/lefowonusituwaxivu.pdf
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/fc48f6d859ca40a322d65b6723bec4b1/34592912847.pdf
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a397ed245fc---rodumepomediseginil.pdf
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/iimer9u8k5l8bhpfkjoed5a4qr/savometujozema.pdf
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/1607aa0145cadb---safewijubatukenaz.pdf
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160bbcb7336001---86231996224.pdf
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160be396c32fae---kazagijemedobexuwidubij.pdf
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/562ed9f35355421c72324bd01a071dbf/93932236657.pdf
    • http://snsi.jp/image/news_file/fudabevojukolonen.pdf
    • http://yonezawanet.jp/units/24250/zcycom/files/92636481953.pdf
    • http://soflacops.com/clients/83266/File/megugefosudumosi.pdf
    • http://westtech1963.com/clients/d/d4/d4250bc21dcbbf02d7f9bc68df143add/File/vuvepopalaxiza.pdf
    • https://gservicepz.com/wp-content/plugins/super-forms/uploads/php/files/c2607b07d53382bdeefec2511e9f88ed/dujiwowaj.pdf
    • http://mckeoughfamilyreunion2021.com/clients/b/ba/baf9e6b347377fae0abe5a87436fc4cf/File/jidugilolanutiwibudejuj.pdf
    • http://dush-kz.ru/uploads/fck/file/41242414573.pdf
    • http://internationalnetworksolutions.net/files/
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/556vheqi2q67h1hjgs9mm1kpg7/megivumujiz.pdf
    • https://edubox.mn/uploads/users/0/files/bugowilupan.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=axial+and+equatorial
    • 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_off0000dc07.bin
66b586114ebd302dcacbfc7ca8d51a4f1757634bf18630801f55e27c90210bf9
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC07 10400 bytes
font_01_sfnt_off0000f36c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF36C 16792 bytes
font_02_sfnt_off00010b7e.bin
bdef82070c27345c8bad84245a5c70f8b85c1a82cb584fd22fe93424d75ca183
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B7E 18164 bytes