Malicious PDF — malware analysis report

Static analysis result for SHA-256 8157608fb6e8588b…

MALICIOUS

PDF

85.0 KB Created: 2021-08-25 04:27:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 994cd8415a8ca3179a41abb6b1495684 SHA-1: 44143dcb3010b43593d79ab759ac8c680ae4367a SHA-256: 8157608fb6e8588b5d2e636aefc597e15cbc5f6860bd83b74908aa5ccc4ce1a4
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised websites, suggesting it acts as a link farm to redirect users to potentially malicious content. The PDF structure and embedded links are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/5feb2eab407d71a322df07202c40568d/vugumo.pdf In PDF document text
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b834cad486b---30966109445.pdfIn PDF document text
    • http://3dprofi.net/images/uploads/file/46415246590.pdfIn PDF document text
    • http://streetnn.ru/data/upload/ck/files/biladitefewegopolibofe.pdfIn PDF document text
    • http://fsoa.cn/userfiles/file/patajebozudinonu.pdfIn PDF document text
    • http://bahattinburyan.com/userfiles/file/3391754634.pdfIn PDF document text
    • https://churchosonline.com/wp-content/plugins/super-forms/uploads/php/files/ae96eaf37c8bf013c7b5a8dae18a188c/11187368506.pdfIn PDF document text
    • https://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/ccc9c380405ebffed4d7754889dcf5be/mebitilapapapovinananemaz.pdfIn PDF document text
    • http://pizzeria-millemiglia.de/app/webroot/img/editor/file/bajigosaromeloz.pdfIn PDF document text
    • http://xn----8sbxab3abskk3a2j.xn--p1ai/media/file/kajarotugarusemojulamobix.pdfIn PDF document text
    • http://hillcresthigh1971.com/clients/9/9f/9fbf9047a6869172a982db6f42f05a9a/File/15991420069.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/160acdfc2bc028---65784930842.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094b386c3bad---60959362467.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/fvevoc8kje4aival6sj75im6d8/kulonofet.pdfIn PDF document text
    • http://aiaato.com/FileData/ckfinder/files/20210801_6BA158BC4E14E1B0.pdfIn PDF document text
    • https://sellerflows.com/wp-content/plugins/super-forms/uploads/php/files/be002925a9aadece427e11c59fd386fd/bapavepedumunibaxaxetejen.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160fd4195b11a5---2053929670.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b3b3ef16d7---39446312925.pdfIn PDF document text
    • https://www.baileysmilk.com/wp-content/plugins/super-forms/uploads/php/files/dd6d6eb25f8835f12d4d5c76a82047a4/6474849372.pdfIn PDF document text
    • http://booklandbooks.com/userfiles/file/jirafaxezo.pdfIn PDF document text
    • https://inchiriereelicopterromania.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160acd78e5d7a3---rurululoxipivijofe.pdfIn PDF document text
    • http://wm-meyer.de/meyer/admin/editor/ckfinder/userfiles/files/bagugavove.pdfIn PDF document text
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/sf9osoqhha5ua0h7nu7g763d36/64751986325.pdfIn PDF document text
    • https://www.webplease.it/wp-content/plugins/super-forms/uploads/php/files/dbuhq6oqo47cg10e0mebl2meb7/70672541888.pdfIn PDF document text
    • http://xn--80aamdqpfpr.xn--p1ai/upload_picture/7234491950.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=read+pdfs+aloud+androidPDF 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_off0000e6e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6E9 17500 bytes
SHA-256: e4689272e19023806755f8c75f074ff7776d9aa97d96f142101ffda0fa152e77
font_01_sfnt_off00011529.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11529 10536 bytes
SHA-256: 1d0df8bcb9cf8e2de20c3c2e11c3cf674c1606b0f0064255d59fbb6635bc835b
font_02_sfnt_off00012d33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D33 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1