Malicious PDF — malware analysis report

Static analysis result for SHA-256 958b133c128db646…

MALICIOUS

PDF

80.5 KB Created: 2021-09-07 09:42:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 59e3e1f09b05610e5a7f088027ca5ecb SHA-1: 21a08c372dd1a1ff6f1a6ca1dd4c23e557d104a5 SHA-256: 958b133c128db646839841a8f4660373aaf6109d145acd27eb99cb66eef78049
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ClamAV and an ML classifier. It contains a link farm with numerous URLs, many pointing to compromised WordPress sites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for these links, suggesting an attempt to distribute malicious content or phish users. The presence of external URIs and compromised CMS uploads points towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://laborke.ru/uplcv?utm_term=manuale+sony+rx100+m5 PDF link annotation
    • https://aimhc.com/userfiles/file/71788434842.pdfIn PDF document text
    • https://snqrsl.quebec/upload/editor/file/pisijakarefukawirijumi.pdfIn PDF document text
    • http://kadh.kr/bobod/upload/file/7100813687.pdfIn PDF document text
    • http://qianxish.com/ckfind_image/files/linobiba.pdfIn PDF document text
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/d52ec3fb40231ef413939e9f79128e03/gufujosal.pdfIn PDF document text
    • https://gradeagroup.com/wp-content/plugins/super-forms/uploads/php/files/hs7jf96qh28ht77mgrsi2tgmos/zifivomatijal.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/85625e435337a33f20b7777def5aa5d6/viwifafejepadiker.pdfIn PDF document text
    • http://z-sinpro.com/upload/files/zilogipukimawekeje.pdfIn PDF document text
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160d7bcd914093---63772697633.pdfIn PDF document text
    • http://dailymaydemtien.com/userfiles/files/janopow.pdfIn PDF document text
    • http://oprandi.it/userfiles/files/texegonulag.pdfIn PDF document text
    • https://monacollection.ua/wp-content/plugins/super-forms/uploads/php/files/3b768385c742b251936b0ddd5665cf9e/rexurufem.pdfIn PDF document text
    • http://mygotour.com/FileData/ckfinder/files/20210529_5481F6474E218CA5.pdfIn PDF document text
    • http://babyindex.nl/images/uploads/vutekerebopukijefafi.pdfIn PDF document text
    • http://ilkyoukais.com/Images/Media/files/fedizuseziveji.pdfIn PDF document text
    • https://www.carnesvarejo.com.br/assets/ckfinder/core/connector/php/uploads/files/fawubite.pdfIn PDF document text
    • http://autodilykanka.cz/cmsimple/images/file/7973943282.pdfIn PDF document text
    • http://pcwenhua.com/uploadimg/file/16231768002097130122.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7f709c4893---musajugijaxazojovejewaz.pdfIn PDF document text
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/v5rlnt9rpeodqb7evrd3bs0e67/87279029937.pdfIn PDF document text
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/28f99bdf7ba599cab1679594ab67ed85/58573616225.pdfIn PDF document text
    • http://win-sonic.com/ck_imgs/files/98900020680.pdfIn PDF document text
    • https://autonoleggioassereto.com/file/44951062965.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607fbf6c82800---wemorejanego.pdfIn PDF document text
    • https://childprotectionindia.com/lexcyberia/userfiles/files/82239458391.pdfIn PDF document text
    • http://asfus.net/virgsurv/userfiles/file/59875983505.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_off0000cbd7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBD7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e3e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3E9 21176 bytes
SHA-256: 2f272fbb450660e4c55f32d21d636538074a7864df701ebc275b86a18918ef45
font_02_sfnt_off00011b9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B9C 10696 bytes
SHA-256: b5b6168d7fbc89a5f4e71c3a2e7f0905bd4050e81f0aaa2ce0066f116b52ff1a