Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a1cb57ac23dabee…

MALICIOUS

PDF

83.0 KB Created: 2021-06-26 04:12:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a6706d2ff96f2a2282af45ad489ccf82 SHA-1: c2e363e5495b1702771d193f498d72291f656d11 SHA-256: 3a1cb57ac23dabeea03177be7ec9129cdb92180e212ec97b98f2fd89958f53b9
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely involving redirection to malicious sites for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://ketchas.ru/uplcv?utm_term=quinn+groundworks+and+construction
    • http://otelm4b.ru/admin/ckfinder/userfiles/files/88385470868.pdf
    • https://www.truegridpaver.com/wp-content/plugins/super-forms/uploads/php/files/9b529044255b1794dbf97dfe12bf55ef/25145013464.pdf
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d585ab1ee3c---47686068728.pdf
    • http://xiaohecollege.com/d/files/mosak.pdf
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1608557a48656b---64218091491.pdf
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6eff03020c---vofupunufesatuwolisu.pdf
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7b9510c8d3---mawar.pdf
    • http://suseefinance.com/userfiles/file/31028186037.pdf
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be471bd2376---sofijirilenejak.pdf
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609c9e8844ea9---59039586631.pdf
    • https://www.opdrrustukalac.com/wp-content/plugins/formcraft/file-upload/server/content/files/160781f208b1f6---pizodafetajimon.pdf
    • http://jun-travel.com/userfiles/file/69181722373.pdf
    • http://bodymindspiritconnection.org/clients/5/53/53f1eac0d8ee32431a47b4e1af774f29/File/gobowopesokabas.pdf
    • https://specialbrands.gr/wp-content/plugins/super-forms/uploads/php/files/9f2f5e02eb5ffffb6aa0be7dcc0681ff/kunowuzegirumebo.pdf
    • http://romanakladatelstvi.cz/userfiles/file/48676880305.pdf
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160824cdb4de41---89298294417.pdf
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/b99bae7efda2ca28fb59890d5b289a38/45872077378.pdf
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/160864d79eed4d---35775304096.pdf
    • http://kingsauto-bar.com/js/upload/files/39682161313.pdf
    • http://veronikavilla.hu/userfiles/file/32366829168.pdf
    • https://www.taxiserviceh24.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608aecf2c5410---zuxijizojobiborimeka.pdf
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089e7132af3d---84142480370.pdf
    • https://empylean.com/wp-content/plugins/super-forms/uploads/php/files/0ditdktp27379sfs8h338bacbp/nimoxibojinibitefowaroro.pdf
    • 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_off0000e123.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE123 16792 bytes
font_01_sfnt_off0000f93a.bin
7bc58efc44dc8f5f3efeac788a5116a4e4f868da37f3668934e8c3126cc4b5cc
pdf-font-stream PDF embedded font (sfnt) at offset 0xF93A 10704 bytes
font_02_sfnt_off000111e4.bin
6dc96ecf2717ff8e602c2294dbf9e380b5925b547e8615d0bc0e932d2606d198
pdf-font-stream PDF embedded font (sfnt) at offset 0x111E4 17132 bytes