Malicious PDF — malware analysis report

Static analysis result for SHA-256 91e116aee51ed84a…

MALICIOUS

PDF

85.2 KB Created: 2021-09-23 22:26:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 2d885e5d2fdb9617f53044dca2733532 SHA-1: d668d0dc3649b62e36c82f7938c96cbf081b5876 SHA-256: 91e116aee51ed84adedae13dba5e4b50359e1c8a7236a29f0f1d46c5f7820cbf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and link farm nature are indicative of techniques used to distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://universitecentrale.net/uploads/FCK_files/file/zewenugedawesovadilo.pdf In PDF document text
    • https://xn--z4qq44i.tw/upload/actfiles/jogim.pdfIn PDF document text
    • http://a-pluset.com/userfiles/valoxasomepujadukasev.pdfIn PDF document text
    • http://wang023spa.com/userfiles/202109file/2021090905010270554.pdfIn PDF document text
    • https://vnjhanoi.com/upload/files/xukakarozisasoviwukabag.pdfIn PDF document text
    • https://mayphotocopydogia.com/upload/files/vezovepikojajinixomo.pdfIn PDF document text
    • http://centroolosprato.it/userfiles/files/xazapepikozibavujuweb.pdfIn PDF document text
    • http://stefanourso.com/public/userfiles/file/wajagate.pdfIn PDF document text
    • https://cqc-material.com/app/webroot/userfiles/files/65798789415.pdfIn PDF document text
    • http://avandcie-energy.fr/ckfinder/userfiles/files/14286423921.pdfIn PDF document text
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/7fd2b55694deb2337879b0e21cf9af97/nedadiwenofonejowejiw.pdfIn PDF document text
    • http://precisionsurgicalworks.com/alpha/ckfinder/userfiles/files/49737161211.pdfIn PDF document text
    • http://capri.lt/userfiles/files/faduvexebareroxenenaxigeb.pdfIn PDF document text
    • http://fongyoskert.hu/userfiles/files/gofariri.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/161347ddd5ce06---bagebuvimedod.pdfIn PDF document text
    • https://sogelec-eng.com/files/ckfinder/files/tafila.pdfIn PDF document text
    • https://kultmotor.hu/images/files/24656809906.pdfIn PDF document text
    • http://elistaprezentow.pl/userfiles/file/xupus.pdfIn PDF document text
    • http://ltmetal.com/userfiles/files/jazifekimufeb.pdfIn PDF document text
    • http://filipdegreef.be/uploads/files/jiwunigozi.pdfIn PDF document text
    • http://www.ortodonciaelisafarache.com/ckfinder/userfiles/files/85134469937.pdfIn PDF document text
    • http://topnotchimports.com/ckfinder/userfiles/files/fonosifuwitosuveze.pdfIn PDF document text
    • http://bukharageorgia.com/sites/default/files/file/faxufaleva.pdfIn PDF document text
    • https://gsacademy.ge/uploads/files/kezomubuzuwegidal.pdfIn PDF document text
    • http://demkapi.com/resimler/files/lalezawunelinixa.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613f1eb819544---daxagin.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=xvr+pro+apkPDF 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_off0000e7ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7AE 9768 bytes
SHA-256: 6e63e31d5b409aa4d591526bdd80fb12009f8dc9d9c45500176a933a59aae3d5
font_01_sfnt_off0000fd20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD20 19128 bytes
SHA-256: 1955896a2919bdbb06d352cf556ac913e99be6a388cd688dc0c27fddf233821f
font_02_sfnt_off00012ef5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12EF5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1