Malicious PDF — malware analysis report

Static analysis result for SHA-256 79b848be10d9fbcf…

MALICIOUS

PDF

84.7 KB Created: 2021-09-22 14:49:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 06430d61d54a85ceecb08d617866c5ad SHA-1: 7ebcf6fad1e5a3032d4ccd133caf8439e670e5f5 SHA-256: 79b848be10d9fbcf511878e2f47fc4a343526d2bb30fef6eb11ea100af4d9154
164 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://catamma.ru/uplcv?utm_term=sticker+emoji+android PDF link annotation
    • http://wjcopy.com/upload/files/tenowozeriw.pdfIn PDF document text
    • https://fajndoktor.cz/images/file/files/89689207867.pdfIn PDF document text
    • http://liyangah.com/Upload/file/wobowerusipumokuw.pdfIn PDF document text
    • https://admonks.ru/wp-content/plugins/super-forms/uploads/php/files/1ecc3b5db540bd12569a338c48b19d07/bubamixegusa.pdfIn PDF document text
    • https://gulfb2b.com/userfiles/file/wasorujavo.pdfIn PDF document text
    • http://qunjl.com/userfiles/files/91240845062.pdfIn PDF document text
    • http://circuitvietnamcambodge.com/hinhanh/file/67118536851.pdfIn PDF document text
    • http://coverybox.box8websites.com/ckfinder/userfiles/files/nozozurikuviwoke.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/10b8082270d9543e829eb6ac41b68df1/21764770319.pdfIn PDF document text
    • https://restavracia02.com/userfiles/file/45980365792.pdfIn PDF document text
    • http://www.deco-interieure.com/userfiles/file/pibufudusoxame.pdfIn PDF document text
    • http://sobinco.cz/ckfinder/userfiles/files/91835822600.pdfIn PDF document text
    • http://beerskiboot.com/img/upload/file/1026777607.pdfIn PDF document text
    • http://sp3siemianowice.pl/userFiles/files/jakoxakazegodonizu.pdfIn PDF document text
    • http://carnow.jp/js/upload/files/42319235612.pdfIn PDF document text
    • https://paradigma.bg/uf/file/77618160008.pdfIn PDF document text
    • http://www.festivalmarrakech.info/wp-content/plugins/formcraft/file-upload/server/content/files/1613a3f7798748---89220590555.pdfIn PDF document text
    • http://lovelyspa.net/ckfinder/userfiles/files/72185064206.pdfIn PDF document text
    • http://instalace-charvat.cz/userfiles/file/wavininepadivejezujopixa.pdfIn PDF document text
    • https://jdsliquorlocker.com/nbloom/fckuploads/file/79566443150.pdfIn PDF document text
    • http://www.binghan.my/userfiles/file/bidukeledunad.pdfIn PDF document text
    • https://www.phuketvillarentalandservices.com/ckfinder/userfiles/files/58036418616.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://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_off0000e5b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5B5 18448 bytes
SHA-256: 9e6b41da8e55d51b946c0c2c266e2e933b6b1875b88cbe206c55c3146325f1e9
font_01_sfnt_off00011532.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11532 10612 bytes
SHA-256: 71cc04851545c9acf357b2ee7525b7df1e2d7e02bbf8b79578a2bac4f2fad850
font_02_sfnt_off00012d6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D6C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1