Malicious PDF — malware analysis report

Static analysis result for SHA-256 86a3b8c4fe0cbad9…

MALICIOUS

PDF

82.4 KB Created: 2021-03-21 08:18:29 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: 133d8ab45a12157249bdf9c7079b9ecd SHA-1: a34f94c7c369b82608ae6ce9c17ad4bf27a95e06 SHA-256: 86a3b8c4fe0cbad9a0fea1729b9b67d4473f2587f2b9cc1768ea47797987290f
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains numerous external links, a common tactic for SEO spam and phishing. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body, though partially corrupted, suggests a lure related to drawing anatomy, which is used to disguise the malicious link farm. No scripts were extracted, but the PDF structure itself facilitates the redirection to malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://maypoin.ru/wix?keyword=el+esqueleto+humano+y+sus+partes+para+dibujar PDF link annotation
    • https://cdn.sqhk.co/dabebasavus/ecWUF1T/duvotupevepopawisibuk.pdfIn PDF document text
    • http://trylait.club/clockwork_angel_series_first_book83kdu.pdfIn PDF document text
    • http://megesodore.iblogger.org/derefatiwepinukozakogafo.pdfIn PDF document text
    • https://cdn.sqhk.co/zezinojox/GBgfijx/sulifa.pdfIn PDF document text
    • http://carbackseat.site/how_to_solve_rubiks_cube_easy_tutorialq9z1f.pdfIn PDF document text
    • https://cdn.sqhk.co/wetabupi/O8ijjjE/14030879027.pdfIn PDF document text
    • http://bcpzonasegur4viabcp.com/kanger_usb_charger_evod_510_thread5b0ve.pdfIn PDF document text
    • https://cdn.sqhk.co/xalesikozip/TFD1Ngd/snes_switch_games_release_date.pdfIn PDF document text
    • https://cdn.sqhk.co/risosejuze/Qdhe1hj/gejidizojo.pdfIn PDF document text
    • http://mkr-olimp.info/what_are_the_benefits_of_a_vibration_machine78iys.pdfIn PDF document text
    • https://cdn.sqhk.co/kamozipu/ixnjjii/vulabafum.pdfIn PDF document text
    • https://cdn.sqhk.co/ninilevikod/oCGAAbl/microscope_labeling_sheet.pdfIn PDF document text
    • https://cdn.sqhk.co/wujozuzewed/ihchegc/futobotufitulatilavawi.pdfIn PDF document text
    • http://kraftmann.su/career_portfolio_template_powerpointvhqkc.pdfIn PDF document text
    • https://cdn.sqhk.co/sejaganetaxa/mXVlUhi/valulozuzokabor.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://3568c1c9-c281-4b9a-9ea9-d5d291e0176b.filesusr.com/ugd/e5d8db_77a729f6ea094d9b9c8bb5e9146ff0c8.pdf?index=trueIn PDF document text
    • https://0ca3454e-05ac-49fc-8d00-644b1af7be3c.filesusr.com/ugd/8bf3fc_fc07120429de4a62bf6848d19bb09644.pdf?index=trueIn PDF document text
    • https://3d73ec66-e24e-4607-99a5-aa3c333c10ea.filesusr.com/ugd/a96454_bf1714a55a1a488da5fe2a003825bfc6.pdf?index=trueIn PDF document text
    • http://mivogunav.rf.gd/mujupudenubaxafu.pdfIn PDF document text
    • https://e4586023-485a-43f1-9451-2d404684c5b7.filesusr.com/ugd/95ff22_fa6c9380751b4665a2113d0bfe7205a0.pdf?index=trueIn PDF document text
    • http://wusumuforibit.epizy.com/butulipuvuwagaridafiz.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_off0000fe56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE56 5600 bytes
SHA-256: 90e3092ad83f6c5dece3a8be5febc16d2e5d963445cbed5c53371812e8dfedf9
font_01_sfnt_off00011139.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11139 12708 bytes
SHA-256: dee751b2b4ca6cca8bbad0cc4ba340982e120693fa09013620bae82c369f6361