Malicious PDF — malware analysis report

Static analysis result for SHA-256 4231330a110cf53e…

MALICIOUS

PDF

69.3 KB Created: 2021-06-12 07:49:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 47c56abc2360f89d2f17e5f9244488bd SHA-1: 863bb4c1d756c2f43f7b74494e79f24efd8f0acc SHA-256: 4231330a110cf53e425836206358879933359c1506004f01f0f2dd069f28d1b2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF document contains numerous external links, many hosted on compromised WordPress sites or disposable domains, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The document body's inclusion of a car sale query and the wkhtmltopdf authoring application suggest a lure to disguise the malicious nature of the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://medvor.ru/uplcv?utm_term=2008+infiniti+g35+coupe+for+sale
    • https://aterhesseg.com/up_image/file/wijiralu.pdf
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/88a4edf2424b1a78b8e02ad6fdc6d9b6/vajogitata.pdf
    • https://radmangroup-ye.com/rgfiles/file/vatodolixukipifaxumone.pdf
    • https://cuisinescartier.ca/upload/editor/file/22581290423.pdf
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/ea82fb372237343e62472ae05acba471/nitotewa.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b0d01281fe3---kokosovesojofa.pdf
    • https://afd.me.uk/wp-content/plugins/super-forms/uploads/php/files/bsq2olf47rh3srej14tp0ir4bs/58081279499.pdf
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a7717b0a96c---libuxorosixininori.pdf
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/98ba8fc0a264ff823beb86bc6b71aa5f/14830081994.pdf
    • http://jjmcp.jp/userfiles/Image/file/65571320761.pdf
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/c492828629f79d7e6fcc8aef68e157d1/47175714240.pdf
    • http://gursakaryahukuk.com/images/file/xivadavukivanoreterabo.pdf
    • http://kulturazebrak.cz/userfiles/kodowirigofasofukonev.pdf
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/atdr5t4gfve59bab6qth2l97j7/dezexegunewibo.pdf
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b13aa44e3a1---4879717229.pdf
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abbf2c8b5a2---somuxijamirivi.pdf
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/31a8gakclff7vrkj8lqh11amu7/61813382689.pdf
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16076822ebaa85---wamabomubemafonibadenore.pdf
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/a4a7c720dcf467a9048bb0de56b6adb4/94295253745.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • 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://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d089.bin
061a416c081e950e21576cca79f0f658f8ce9cd795981ea7a824f901896977cd
pdf-font-stream PDF embedded font (sfnt) at offset 0xD089 5844 bytes
font_01_sfnt_off0000e481.bin
ba25f3000510e59e20d05b23f129f56d579d3b655aa8d89097a438732c5ab8a9
pdf-font-stream PDF embedded font (sfnt) at offset 0xE481 10348 bytes