Malicious PDF — malware analysis report

Static analysis result for SHA-256 4501b25eaf397bff…

MALICIOUS

PDF

76.5 KB Created: 2021-03-06 22:42:50 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-20
MD5: 02bdfb817ed97b07db50a5936dc2e68c SHA-1: 5b8ed89883d6b259ad0237d7bf6492625c5ca7aa SHA-256: 4501b25eaf397bff7e9a62895d6b982639dce26e588b5dd687438ef6cfc55f7b
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, identified as a link farm, directing users to various PDF files on different domains. This behavior, combined with ML and ClamAV detections, strongly suggests a malicious intent, likely for SEO manipulation or to distribute further malware. No scripts were extracted, and the document body was heavily obfuscated, making a precise family attribution impossible.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://leonvi.ru/123?utm_term=guitar+songbook+with+chords+pdf PDF link annotation
    • https://belatefa.weebly.com/uploads/1/3/0/7/130775380/8591005.pdfIn PDF document text
    • http://penageli.getenjoyment.net/skill_set_or_skill-set.pdfIn PDF document text
    • https://vaxatimiroxak.weebly.com/uploads/1/3/4/6/134617636/5109806.pdfIn PDF document text
    • http://mozaduz.mygamesonline.org/98798204987.pdfIn PDF document text
    • http://nipokaxa.getenjoyment.net/brandon_marshall_fs1_contract.pdfIn PDF document text
    • https://xufalawat.weebly.com/uploads/1/3/0/8/130814535/fewob.pdfIn PDF document text
    • https://ramakizuwag.weebly.com/uploads/1/3/4/3/134321509/vatimupefeli.pdfIn PDF document text
    • http://tuvivukaroj.mygamesonline.org/bhagavad_gita_chapter_11_in_english.pdfIn PDF document text
    • https://mamapesuwilataj.weebly.com/uploads/1/3/4/8/134857931/1080460.pdfIn PDF document text
    • https://toripifisesu.weebly.com/uploads/1/3/4/3/134367164/giregoloxoluzir-peperomamopikub.pdfIn PDF document text
    • http://kudukudimox.sportsontheweb.net/casio_g-shock_multiband_6_tough_solar_instrucciones.pdfIn PDF document text
    • https://sanepawoja.weebly.com/uploads/1/3/4/5/134579143/nagivibutiwefomafud.pdfIn PDF document text
    • http://fudoviwil.mywebcommunity.org/wisonepubozejiv.pdfIn PDF document text
    • https://donabetolemi.weebly.com/uploads/1/3/1/6/131637402/0849074.pdfIn PDF document text
    • https://gemitipob.weebly.com/uploads/1/3/4/4/134474898/2279395.pdfIn PDF document text
    • https://xezatitewifesel.weebly.com/uploads/1/3/4/3/134393938/5420005.pdfIn PDF document text
    • http://nageramuvepom.mywebcommunity.org/which_processor_is_best_in_i5.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://benamow.myartsonline.com/soxupefekuwupitawis.pdfIn PDF document text
    • https://5071cc05-3fa2-46b1-b944-d2523ca4b51d.filesusr.com/ugd/62e2c1_695d7e09c98943eeb36c5e5496ae9977.pdf?index=trueIn PDF document text
    • https://5053e88e-9e18-4719-890c-32a1cca0295d.filesusr.com/ugd/411503_265bafc476f34404b8f8c1b07bd0e94b.pdf?index=trueIn PDF document text
    • https://7f06b679-e14d-4525-8955-d56a7cf6f710.filesusr.com/ugd/79e5df_fbf56864f9bc41a19a7192a4d827a188.pdf?index=trueIn PDF document text
    • http://jalebuvubo.myartsonline.com/63672396861.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ed3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED3F 5712 bytes
SHA-256: 494fc533ac14a92b2e8669895446ed655b101354dd44e0a725d07a90008d9669
font_01_sfnt_off000100c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100C6 10440 bytes
SHA-256: 4079a958593822672e4df56d0bedd561ac8d4601d2d49dc20186757f21df0514