Malicious PDF — malware analysis report

Static analysis result for SHA-256 51f8a6bcb4c3515b…

MALICIOUS

PDF

85.7 KB Created: 2021-07-13 18:54:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: dff4cd1cc33294cda89118bbf8c1bbce SHA-1: c360de6760d1d58f60efa2bf76a5edf98063d813 SHA-256: 51f8a6bcb4c3515b79dee0dc45f029fce4fa96b085fec3465a9cb6e01a241f14
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://laborke.ru/uplcv?utm_term=free+porn+games+on+ios
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/a2aptbeoep98kp75bg2tqm2u6e/raviwerebefelafabesapus.pdf
    • https://cochleartudaskozpont.hufiles/96464927842.pdf
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080467c26c1e---banuzodawabenezazufov.pdf
    • https://bbpartner.cz/userfiles/file/35546746326.pdf
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072394d6ab49---jorolo.pdf
    • https://asiajitutop.com/contents//files/99251928609.pdf
    • http://apartamentosalbatros.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd216647402---sinixefige.pdf
    • http://farashimirooz.com/files/4434290010.pdf
    • http://lightningriskassessment.com/ci/userfiles/files/23410919706.pdf
    • http://falconartistmanagement.com/ckfinder/userfiles/files/timaledoteliti.pdf
    • https://alzubidi.com/userfiles/files/42382635485.pdf
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/35m2nkqagshhbg2n2mlm0ks0su/16638996773.pdf
    • http://vintageguitar.ru/ckfinder/userfiles/files/dobirasigisuletuzapexuv.pdf
    • http://morecoredesign.com/images/imageUps/files/gewujorigoditivawenu.pdf
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160ec4494d031a---10629007327.pdf
    • https://registracijakoncar.com/webroot/js/ckfinder/userfiles/files/zokasowatefaw.pdf
    • http://fewo-spreewald-schoetzigk.de/brandenburgtag/img/editor/file/totipitipa.pdf
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a397a5098b---xodopadivexaketavozat.pdf
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/f1ppgqgd6c3v1ou7i47jtv4avk/46076217933.pdf
    • http://aligokdemir.com/resimler/files/95676367677.pdf
    • https://ficsllc.com/wp-content/plugins/super-forms/uploads/php/files/arqcf1gd1ni9fs3tat4ctfvg2n/wolajigozigerofe.pdf
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cc96b94ef61---wegifukomotatumoru.pdf
    • http://xn--80aaeiengkwpz6p.xn--p1ai/pub/file/40930407120.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_off0000ebb8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEBB8 16792 bytes
font_01_sfnt_off000103ca.bin
a5f4df9c99d5bf6e4c7e0a015835074b12a0e31ee7250abc3b108ad33ea7aa7e
pdf-font-stream PDF embedded font (sfnt) at offset 0x103CA 17216 bytes
font_02_sfnt_off0001309a.bin
fa6b81887ceebcfb1b0e5bc32da4ef768f2f3306fd6185c34fb3581fdc190729
pdf-font-stream PDF embedded font (sfnt) at offset 0x1309A 10428 bytes