Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8436112f29c5bfa…

MALICIOUS

PDF

85.8 KB Created: 2021-07-01 22:33:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: aeee4d50ed437d303169ddfaeab83973 SHA-1: 70d3530a2ba5f2c071a4a24c08b0b0c246970016 SHA-256: f8436112f29c5bfae3d3536c787bf940fdf9a9bdc21026c7a7680d3d7dddf761
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links to external websites, many of which are hosted on compromised WordPress sites, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URLs point to a common tactic of using documents to host redirectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://krisoc.ru/uplcv?utm_term=harry+potter+goblet+of+fire+movie+download
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/757tj556ulv1gqgl8ljngfll01/wudevidevito.pdf
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160c4e70805010---voxuvegokujamaserus.pdf
    • https://stratasphere.online/userfiles/file/timuzaporote.pdf
    • https://branchennachweis.eu/userfiles/file/74684628343.pdf
    • http://adams-gold.ru/archive/image/file/55807176589.pdf
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1608e9831a5492---10164463856.pdf
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160baaef6ad3fb---75070214343.pdf
    • http://bettaletroom.com/file_media/file_image/file/68431797260.pdf
    • https://markyatirim.com/resimler/files/jarorivolidivanudalo.pdf
    • http://barsugo.com/ckfinder/userfiles/files/18559038374.pdf
    • https://sygimportaciones.com/wp-content/plugins/super-forms/uploads/php/files/7ae27mb1t9i4unslh9i2os72v0/xetorej.pdf
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/160741ba6b60f9---wewox.pdf
    • http://www.jobsincrete.gr/images/_user_na/file/zujadikodu.pdf
    • http://iwish-cosmetics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5615d96af3---22264611466.pdf
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160b392fd35b3f---gasejifaserigerisux.pdf
    • https://baoholaodong24.com/userfiles/file/57763256886.pdf
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/4pcr4mkqfhaq81kpf7j5ss3aa2/fonuzefuf.pdf
    • http://amexeuro.com/an3_Uploads/file/70330320984.pdf
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/2c3c9035c54f5ea9aca6bbf70acd8360/nozonerupajalamuwefemal.pdf
    • http://etcad.net/np/upfile/file/97689473523.pdf
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c8530abe7d---naxalulixekukivomunoz.pdf
    • http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a956544e951---liligutazetunopuvivele.pdf
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/3ggdik5dg8vjuf7cp52ib0i0nv/mazeniresekojelanujewez.pdf
    • https://oumkua.com/userfiles/file/98004842058.pdf
    • https://agrilaui.com/userfiles/file/mezag.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_off0000e988.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE988 16792 bytes
font_01_sfnt_off0001019f.bin
d760295dc4e3396243fd1c19da89c9c0f3ae00c8b47e512094a8e548d558acbf
pdf-font-stream PDF embedded font (sfnt) at offset 0x1019F 11072 bytes
font_02_sfnt_off00011af6.bin
7e449b69c08468c209d5d1eba1c5881a08a2edc1458f0daed02275f05ab9d75f
pdf-font-stream PDF embedded font (sfnt) at offset 0x11AF6 18004 bytes