Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a3c1563bdc11cab…

MALICIOUS

PDF

85.6 KB Created: 2021-06-26 13:57:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f77aeeac81c6506b30164bd90c4f9b23 SHA-1: 795500c1ef82517a7529f5a6847dd6d6b2a79dfa SHA-256: 1a3c1563bdc11cab50fd578d718cfecf6e024457d78cf062c92b9f5d72694db0
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. The heuristics indicate the PDF acts as a link farm, directing users to compromised WordPress upload storage and other disposable hosting. These links are likely intended to deliver phishing content or further malware stages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://olmitek.by/wp-content/plugins/super-forms/uploads/php/files/4j9er16rva84ueo5bb4nn137b2/rigokedekikeresarabiraz.pdf
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/hjqkr3a6fcaf58ouet0kumuo26/wawisodofiwivaxexolisotis.pdf
    • http://prmakeup.com/Image/files/40295412202.pdf
    • http://sola-brothers.com/userfiles/file/vosufakufevimazetalelix.pdf
    • http://tai-yang.tw/taiyang/upload/file/49431096380.pdf
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a7029734182---gopovonuzazizuk.pdf
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608023488e03c---90388768999.pdf
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/6c92974adcdb146d6f8bcdf6852946b5/sugajor.pdf
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b05034803f4---4273326647.pdf
    • https://glowskincare.net/wp-content/plugins/super-forms/uploads/php/files/e4bd0be2f5d36d65e577e510c19a2444/xesegefolekisujumaxipori.pdf
    • https://coloreverything.love/wp-content/plugins/super-forms/uploads/php/files/1685353a62c977a69e58d1e978b8d233/93473032306.pdf
    • http://clinicaveterinariasangiacomo.it/userfiles/files/24435937375.pdf
    • http://xboxheerlen.nl/userfiles/file/44875416181.pdf
    • http://www.everhouse.lt/wp-content/plugins/formcraft/file-upload/server/content/files/16099c2077a220---94823594488.pdf
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608f08f4795f0---82979225624.pdf
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607edb14684b1---tavaxefifa.pdf
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/4om9v964fm82l0ksokds2d9kn2/95545249593.pdf
    • http://wtmongolia.com/materials/file/65037560377.pdf
    • http://articolo17.it/siti//usr/foto/files/wokuxenuzajuwekudaditobum.pdf
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/k0oi4hdmln7abdvkt3l7dcmlg0/65957625251.pdf
    • http://zoltysnieg.pl/pliki_wyswig/files/1789143496.pdf
    • http://tikatalog.sk/_files/file/78263925731.pdf
    • http://yakutiaprime.ru/SITE/files/editor/file/durorekuvatafefejoror.pdf
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/c0b4f0ead059c65398937cd06aa0c996/32660049055.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=circulatory+system+test+answers
    • 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_off0000e8c2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE8C2 16792 bytes
font_01_sfnt_off000100d4.bin
59694c29beb8dc256b64d31bf87d41a8c4600a63dc30ba97e0a0fb37106577ec
pdf-font-stream PDF embedded font (sfnt) at offset 0x100D4 17524 bytes
font_02_sfnt_off00012efb.bin
638076ca04b54adb1dbedf6b7facf12a36a63328f19922a93f98ee58df2ec906
pdf-font-stream PDF embedded font (sfnt) at offset 0x12EFB 10720 bytes