Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b7f05b8db2d356f…

MALICIOUS

PDF

70.1 KB Created: 2021-09-07 10:20:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f4084c251c3464f08941111951ebf62f SHA-1: 2e69e6aad1c0a83144155d8d1d811bfc560cc577 SHA-256: 1b7f05b8db2d356f03705d88a86b2ceb0cd753218739b934a0684785fda6d6a1
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress sites and appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/160a514bc84743---61239175134.pdf
    • http://vitacanes.com/uploads/files/pebalutoxozusibiwitox.pdf
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609f36a14e5c5---28225868187.pdf
    • http://gillsandgeckos.com/userfiles/file/lebulev.pdf
    • https://nenanhduong.vn/Upload/files/41317918047.pdf
    • http://reguitti-engineering.it/userfiles/files/kijenojeki.pdf
    • http://viral-list-machine.com/ckfinder/userfiles/publics/files/78357902464.pdf
    • http://doublehappyvstheinfinitesadness.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a59c5265f5f---79783022523.pdf
    • http://www.mywil.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1608b015a58c92---sabulatekuxeduzakomiv.pdf
    • https://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/a0f6f49db7ed4d072c3276c908641c66/sidelifetepikegutijasug.pdf
    • http://innovatepc.com/userfiles/file/32056366687.pdf
    • https://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/cdf7aa4e09a78229aadf39066c8bc340/75078821077.pdf
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/r37cb4c57v5i8h7rolk77ee5uh/21086481358.pdf
    • http://popnmusic.fr/userfiles/file/pevusunubugotobavagig.pdf
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160c4cf61e3efb---kikisof.pdf
    • http://www.advokat.com/app/webroot/img/fck/file/16142892721.pdf
    • https://hinodanang.com/uploads/image/files/kutorazedixinelesazudevak.pdf
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607e49af89551---33444324625.pdf
    • http://verynailscm.com/user_img/file/viwatemezolu.pdf
    • http://meruzhankhachatryan.com/app/webroot/files/file/rotebufevewibalotatina.pdf
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/94d7a767ec62196370b99be3f10a7036/68615923538.pdf
    • http://www.companyforte.com/imagenes/editor/file/xuvirivopoxotanalimitat.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=inside+job+video+worksheet+answers
    • 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_off0000b2e2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB2E2 16792 bytes
font_01_sfnt_off0000caf4.bin
9c9bc551da9af616fd28c11002bd9d8cf63d5a4545e2252e60b47082915c5351
pdf-font-stream PDF embedded font (sfnt) at offset 0xCAF4 15160 bytes
font_02_sfnt_off0000f1a9.bin
360acd456b54f2028fc7dc1a593a3adc124904eba286820b01c3d171c018d13b
pdf-font-stream PDF embedded font (sfnt) at offset 0xF1A9 10764 bytes