Malicious PDF — malware analysis report

Static analysis result for SHA-256 23d5f7b21de3bfc5…

MALICIOUS

PDF

85.3 KB Created: 2021-06-30 01:21:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d44f3dde33ff3dec891271ec95398997 SHA-1: 3e72ab10e20b4194c4a7cc45d6c1eafebf22a39b SHA-256: 23d5f7b21de3bfc5b5c6d0dcc2cd90efdf6abe73f0ed29e18aae86a6ea51d175
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of link farms on disposable hosting and compromised CMS uploads suggests a tactic to obscure the ultimate destination and evade detection.

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://catamma.ru/uplcv?utm_term=weak+acid+strong+base+titration+equivalence+point+calculation
    • http://theeultimatenetworker.com/ckfinder/userfiles/files/47248378032.pdf
    • https://yziact.fr/wp-content/plugins/super-forms/uploads/php/files/vem3ldk7vm71sdledkib6j5ecn/ladoxesikede.pdf
    • https://tiklatakip.com/calisma2/files/uploads/28303702221.pdf
    • https://blugarden.eu/file/zebapamutenimawax.pdf
    • https://shellserva.nl/docs/Image/file/nedunuvitebef.pdf
    • http://www.jamesbgriffinlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0750751d8b---49206746750.pdf
    • http://gloucesterclassof81.com/clients/23558/File/30449402707.pdf
    • https://lightingsystemscol.com/wp-content/plugins/super-forms/uploads/php/files/4ac278659715b88aeff1118b8bdab9d6/31793795865.pdf
    • https://www.lightingdynamics.com/wp-content/plugins/super-forms/uploads/php/files/cebe765b42edd2b0511a4a636de38108/23841819120.pdf
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d21debbedc7---71699988498.pdf
    • http://dianacb.cz/userfiles/file/viful.pdf
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/89ded56412ecf5dcc110fb3af85a5bde/gisokari.pdf
    • http://strefa-fitness.pl//fckeditor/editor/filemanager/connectors/phpplikifile/pasubezofajonopanuxax.pdf
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607232eb9dde7---nuxaluzawud.pdf
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/e06f2440181df2d426e761cd402e5d34/33697149028.pdf
    • http://diagnosticaedilizia.com/userfiles/files/voxinaxibob.pdf
    • https://hashtag.school/userfiles/file/tokesepufotigebuzimar.pdf
    • http://hoitruyengiaocodocvietnam.com/uploads/image/files/navulemeguzuva.pdf
    • https://www.rowtheerne.com/wp-content/plugins/super-forms/uploads/php/files/379d0adc23dfdbc1c44a6348279944c7/padaxavado.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cef323151dc---23720790478.pdf
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160a17633331f6---41722749701.pdf
    • http://orgue-chantepie.info/FCKeditor/upload/file/45981559941.pdf
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/142qb04p5rdbf8ssbqipqqq4ti/wedezujodarevemivafon.pdf
    • http://zoltysnieg.pl/pliki_wyswig/files/fepozesofefu.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_off0000eacd.bin
a1ea69ded8f346b212a9249aa673f6a27c40cefdfd41fbc536b76421e788108a
pdf-font-stream PDF embedded font (sfnt) at offset 0xEACD 11224 bytes
font_01_sfnt_off00010483.bin
20eae82f038664d8009d109445c3d58e060d2ba40f46179c920b032f06e32925
pdf-font-stream PDF embedded font (sfnt) at offset 0x10483 16500 bytes
font_02_sfnt_off00012f5c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F5C 16792 bytes