Malicious PDF — malware analysis report

Static analysis result for SHA-256 793a94a2493d3203…

MALICIOUS

PDF

96.6 KB Created: 2021-07-02 14:46:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: dacc99ffa08fd53f7f0f344598d206cf SHA-1: 8d68ac42d56fd335eeb012edf7eba2cdaa5bef01 SHA-256: 793a94a2493d32037af9639f9ec95d80f4ddeac38b04d9b4efc3b6d27a9a10e3
224 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The PDF contains numerous links to compromised WordPress sites, suggesting it is part of a link farm designed to distribute malicious files. Heuristics indicate it uses urgency and recovery secret lures to trick users into downloading the file. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Recovery secret / private key request critical SE_SECRET_RECOVERY_LURE
    Document requests recovery phrases, private keys, backup codes, or saved passwords. Requests for these secrets in a document are high-risk.
  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/16089e238ec435---wadosu.pdf In PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/f1ed6d9c96cf5451fee3d5e3b9b0e6af/konafinilidifuju.pdfIn PDF document text
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/042fef666f15fff182f8218030d89fc5/57208039842.pdfIn PDF document text
    • https://palcev.ru/userfiles/file/94981101263.pdfIn PDF document text
    • http://sushinamu.com/uploads/files/38795497066.pdfIn PDF document text
    • http://coffee33.ru/archive/file/jewuduteter.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bd38fbed267---92292379328.pdfIn PDF document text
    • https://electrabicycles.pl/app/webroot/uploads/file/16229233313116.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7f44f57096---xiduzujiguzilonapudoket.pdfIn PDF document text
    • http://mazdooradda.com/userfiles/file/kopapam.pdfIn PDF document text
    • https://morethancleaningservices.com/wp-content/plugins/super-forms/uploads/php/files/e96ba48829d739ae7d412bde25121137/24550479160.pdfIn PDF document text
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b287f8222e2---6070133038.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cb4a1f2eeb---pubaje.pdfIn PDF document text
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/90d47750809449006f7902f157cfa4af/renujituzedi.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/9a2ccf1cdae5754812be9d983d723cde/gixaxaz.pdfIn PDF document text
    • http://burgas-remonti.com/userfiles/file/bekubopegazefosizizi.pdfIn PDF document text
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160be71e0e506b---96427591954.pdfIn PDF document text
    • https://imotrading.com/images/userfiles/2028307969.pdfIn PDF document text
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/0e3c8568e0c396f89756eb3ed759211c/10065877143.pdfIn PDF document text
    • http://anhuizpyy.com/upload_fck/file/2021-6-16/20210616030913144997.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090eff6e8cf4---jidedi.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c03d89f338e---41526811073.pdfIn PDF document text
    • https://proxus.nl/file/denopuxageverekejoza.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088d649395ae---64552937422.pdfIn PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/740e15a45335fb32d54ba1cd957d3770/dubabup.pdfIn PDF document text
    • https://roweryelectra.eu/app/webroot/uploads/file/16199507070688.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=encrypt+online+with+keyPDF 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_off0001160f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1160F 18048 bytes
SHA-256: d446c04b707bb7823a16f08a40095d01356d0d50c01f6bf4217c536fbf52dfe7
font_01_sfnt_off0001458b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1458B 10416 bytes
SHA-256: 6187d367bf67005db1ad9d013a69753bc20fa8f40a602b6851a973480414660a
font_02_sfnt_off00015d15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15D15 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1