Malicious PDF — malware analysis report

Static analysis result for SHA-256 e3653c5ebef56395…

MALICIOUS

PDF

70.4 KB Created: 2021-09-03 07:08:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d0e4b488ca29a4bb1fc10ecebfe66abf SHA-1: ea4c81ff897b53adb4ae9393d49d48d31350538c SHA-256: e3653c5ebef56395c775ef3f17a01d869ff04e1f6fcae36d3521c6afff15311d
176 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many pointing to compromised WordPress installations or disposable domains, suggesting a link farm designed to redirect users to malicious content. ClamAV detected this file as Pdf.Phishing.Trojan, and ML classification strongly indicated maliciousness. The primary attack pattern involves directing users to external resources via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://kursadowicz.pl/Upload/file/306356385.pdf
    • https://digireg.si/upload/votudutibozevoj.pdf
    • http://digemnd.com/UserFiles/file/25199722427.pdf
    • http://polkovnik.su/upload/file/xositebejitefipirotune.pdf
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c8f8a81fb22---17875756535.pdf
    • https://steklo-shik.ru/userfiles/file/tazozages.pdf
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/5ab14fc8e21a64fb1281b02d56d93121/kelemez.pdf
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/383bd61c724e5c0cc9e2117553176c41/zekix.pdf
    • http://79.170.40.182/boothtastic.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096dd0183f8b---bozomawazuzadajesemuk.pdf
    • https://al-wesam.com/userfiles/files/65047309667.pdf
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/d53969b7352c1244d825317d21e4c6f3/sulever.pdf
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b02fe17fd00---kamisonebe.pdf
    • http://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1607a924467f92---xapuramunasasikamoveb.pdf
    • http://www.findvoters.com/userfiles/file/50648646795.pdf
    • http://hwayinn.com/image/files/20210826_031423.pdf
    • https://unosms.us/userfiles/file/disabivukodobixir.pdf
    • http://historia-bfured.hu/userfiles/file/soberev.pdf
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/1d6b670ef6ccf0ade5808baa2921a5b1/90931946752.pdf
    • http://thucphamchucnangmy.vn/uploads/files/89202492427.pdf
    • http://ifaistos.reality.gr/~triantaf/images/file/49153364272.pdf
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/5isjonqnliucvlls0fl0t5i86m/vapexowelokubafu.pdf
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/16080a5c939066---94599460734.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=aerating+your+lawn+manually
    • 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_off0000b509.bin
45eb01f77060dbe6535dd460242b8692d0350b8af527da70c1726a8c3ce800f6
pdf-font-stream PDF embedded font (sfnt) at offset 0xB509 10564 bytes
font_01_sfnt_off0000cd30.bin
ec03749ae383046f18c01a0a03ac913733d86d7b5531e6a7d1392ca9b4215a46
pdf-font-stream PDF embedded font (sfnt) at offset 0xCD30 15276 bytes
font_02_sfnt_off0000f3ad.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF3AD 16792 bytes