Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac24f4db8e8f143d…

MALICIOUS

PDF

87.8 KB Created: 2021-08-20 04:17:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1e75a945614b626424ec7b30e0dc30a5 SHA-1: b615d7b5d91e2273318e849ff27bbd841ee9673d SHA-256: ac24f4db8e8f143d75ac1fc77d7066379bf43e2ea6f590aa92c5e706c9cccc01
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document containing embedded JavaScript, which is a common technique for executing malicious code. The presence of numerous external links, many pointing to compromised WordPress sites, strongly suggests a phishing or redirection campaign. The ML classifier and ClamAV detection further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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 http://cupta.org/userfiles/files/20210528154259.pdf
    • https://amerismithenterprises.com/wp-content/plugins/super-forms/uploads/php/files/c3550018d11f483c8dbc56fb11311d7e/36756799131.pdf
    • http://www.portofmiamitunnel.com/system/js/back/ckfinder/userfiles/files/zajuviteseve.pdf
    • http://php-lounge.de/userfiles/file/wizopadavad.pdf
    • https://www.oneirishrover.com/wp-content/plugins/super-forms/uploads/php/files/78bf8ce8b9f079cde236de321f0abbb7/39389469644.pdf
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8a43512637---35549383353.pdf
    • http://spearmanhsreunion.org/clients/e/e1/e1754705b4c076d7cd520c5e9e79ed07/File/vawerixupaputuwonomokoxom.pdf
    • https://glowskincare.net/wp-content/plugins/super-forms/uploads/php/files/d6de76bdecc6dc134a7049033a83e918/tigedunulexulojagenorekeg.pdf
    • http://airelimpio.mx/img/editor/file/judodoruweduzegujude.pdf
    • http://grapevinewinerytrail.com/clients/876125/File/tuluxugozinagodebi.pdf
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b05cab87190---42307638881.pdf
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160beea9836545---25331062860.pdf
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/7970453ab21fe1df939c4401c30eeb51/nudigokejom.pdf
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/16085972421854---26725723200.pdf
    • http://xn--80aguejfegacgj0ad.xn--p1ai/pict/file/kuluxunidozemov.pdf
    • https://magyar-logyogyasz.hu/fileok/file/daperimuvomup.pdf
    • https://coluer.ir/documents/file/52486687483.pdf
    • http://fashioncenterpoint.com/wp-content/plugins/super-forms/uploads/php/files/bf038a51fb0aa686ad709a9b6ac0c802/rutiwadabufe.pdf
    • http://gabortech.comadmin/file/nelol.pdf
    • http://kroonzuivel.nl/ckfinder/userfiles/files/12775038157.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=ejercicios+de+sumas+y+restas+con+la+ley+de+los+signos+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_off0000ee36.bin
6d8c9ed906453a5105f32cc7b1fed7083276c52af4edd7b216c927c9edf42a19
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE36 11288 bytes
font_01_sfnt_off00010882.bin
465624a305fbed4ae7858056bbd8f1817467cecd6c69ea6b57d9f0a8e72d89c9
pdf-font-stream PDF embedded font (sfnt) at offset 0x10882 18056 bytes
font_02_sfnt_off0001369f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1369F 16792 bytes