Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8508f77bacdd778…

MALICIOUS

PDF

90.3 KB Created: 2021-08-14 17:44:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 0931ef0ff0f3bc9074396b1b6c717bdf SHA-1: f7f6dcf1f6ce23f8c18548147453f6ba52edae90 SHA-256: a8508f77bacdd778fc2f5177e4aeb8e02ad777c0bbc94d1663708a2209312f9e
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to compromised WordPress sites and disposable domains, a common tactic for phishing or distributing malware. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or a trojan downloader. No scripts were extracted, and the document body was unreadable, limiting further analysis of the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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://fipjp.com/userfiles/file/77235589802.pdf In PDF document text
    • https://www.andrecampbell.ca/wp-content/plugins/super-forms/uploads/php/files/5265fc20f2b2017c8fb553baf4a36888/bepifuxafejukopexunuze.pdfIn PDF document text
    • http://systemsbiology.at/uploads/assets/file/vilupukugazavipikugaxuta.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160854cbd4132e---xagudafu.pdfIn PDF document text
    • https://joefairless.com/wp-content/plugins/super-forms/uploads/php/files/894d88fb437ac6f95ebd1638c2c8817a/bojubugibafep.pdfIn PDF document text
    • https://digireg.cz/upload/varoz.pdfIn PDF document text
    • http://dailyliving.nl/ckfinder/userfiles/files/83505981687.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c67d37b3c78---75548802431.pdfIn PDF document text
    • http://fashioncenterpoint.com/wp-content/plugins/super-forms/uploads/php/files/b0c9501189605e96df0f71c6489d7794/zamotuxazexivunixarifi.pdfIn PDF document text
    • http://soudurelauziere.com/upload/editor/file/mejoxomuxuvajamoj.pdfIn PDF document text
    • http://atut-biuro.com/uploaded/file/ligabezivatomobap.pdfIn PDF document text
    • https://www.vbclighting.com/wp-content/plugins/super-forms/uploads/php/files/727ef9e5f4739ccc0b6eb92aac6cff83/bukosunijisulitokurezapo.pdfIn PDF document text
    • http://utopbrake.com/uploadfile/files/vexewolinefetevapemezo.pdfIn PDF document text
    • https://ipcare.nl/wp-content/plugins/super-forms/uploads/php/files/hs1kcf8tj0e8ldrjk3fn63g538/89938129615.pdfIn PDF document text
    • https://haidangpc.com/contents/files/98891334230.pdfIn PDF document text
    • http://techbis.pl/files/file/zapolew.pdfIn PDF document text
    • https://haltia.mx/sii/ckfinder/userfiles/files/16694687541.pdfIn PDF document text
    • https://luxmarketing.agency/wp-content/plugins/super-forms/uploads/php/files/97i59vo3oep411klev9mcogov2/womulovomaduzopumuki.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/7h083dhucbag45vulcq7a57pp7/658101244.pdfIn PDF document text
    • https://www.gullyracing.it/admin/ckfinder/userfiles/files/jirikebuwinimexexotifam.pdfIn PDF document text
    • http://beiwendq.com//data/attachment/file/31124022240.pdfIn PDF document text
    • https://www.baust.edu.bd/app/webroot/ckfinder/userfiles/files/fifizetoxinerugajikedu.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/6caa711cd116c38c23bdf3b2e84ca9bb/pigajuvege.pdfIn PDF document text
    • https://thibiditrading.com/public/userupload/files/87568467349.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=licencias+eset+nod32+antivirus+gratis+2020PDF 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_off0000f84e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF84E 11036 bytes
SHA-256: cd64a732d6216b4c090026e7fa6eb2ed1c7b3f50cef1c560980724b2f517abc8
font_01_sfnt_off00011203.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11203 18136 bytes
SHA-256: 7304ca889b93220d62f6c4765bc8c80acfc1c10151b946a285d96ef53c4e1345
font_02_sfnt_off00014023.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14023 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1