Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a0b7a80cf7dec61…

MALICIOUS

PDF

88.1 KB Created: 2021-08-01 11:32:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 09c06b78c71a8abc1e73abf347032084 SHA-1: f3b721c2afd934a9a0ee3a5919a331da692efaf4 SHA-256: 3a0b7a80cf7dec619e5c985d1a68d7401b23af5f0d0748d950cde404e67a7216
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links pointing to compromised WordPress upload storage and other disposable hosting, suggesting a link farm designed to redirect users. The presence of a download button lure further supports a malicious intent to trick users into visiting these sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://kede.org/userfiles/file/15688745831.pdf In PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/1608ec58c817bc---tozisonipimetoduvusug.pdfIn PDF document text
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cdba0d7a13---95837675974.pdfIn PDF document text
    • http://pneusmarene.it/images/file/musesebajijokofidujofuvot.pdfIn PDF document text
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/34c43fccf0083033c69c0e654b1898d9/felugumedisiwok.pdfIn PDF document text
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/c9as8pephv3le044re8m5lmhe4/44583472862.pdfIn PDF document text
    • http://hyosangjo.com/userfiles/file/20210729211656.pdfIn PDF document text
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/21f43d9c45eed458a97dab0ae738942c/82143456869.pdfIn PDF document text
    • http://singer-island-condos.com/userfiles/files/jejet.pdfIn PDF document text
    • https://hosvagyok.hu/userfiles/file/lexikelaxekanemebewu.pdfIn PDF document text
    • https://0900107678.com/upload/file/28114892290.pdfIn PDF document text
    • https://alixdemassy.fr/userfiles/file/69082552796.pdfIn PDF document text
    • http://uk-finansist.ru/userfiles/file/lapurox.pdfIn PDF document text
    • http://topenglish.sk/app/webroot/gallery/files/legek.pdfIn PDF document text
    • http://hoangminhphatkorea.com/webroot/img/files/jilarisiwisepamafe.pdfIn PDF document text
    • https://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b610f97d9be---kujegesusesomivexuvam.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/ba18955d193c81b8020061b7296c0d68/32842121764.pdfIn PDF document text
    • https://actor-conseil.com/files/file/86711185153.pdfIn PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078c4f2ab6e7---55446629560.pdfIn PDF document text
    • http://metaglas.kr/userData/board/file/wujidud.pdfIn PDF document text
    • https://iiml-pgpsm.in/ckfinder/uploads/userfiles/files/guluvuxitamavuw.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/160c49d7d928e3---10178770100.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=aceable+final+exam+answers+texasPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f221.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF221 10684 bytes
SHA-256: 2bdea9e5a150ce3d70f71995be12c4b7ff10b23e20cea363eef60dcd30c97645
font_01_sfnt_off00010aaa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AAA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000122bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122BC 17772 bytes
SHA-256: ec19c09dbde6067ec8b88b5a171f8430879f496410cd923a07c728943afd51ae