Malicious PDF — malware analysis report

Static analysis result for SHA-256 c167f794cd57b9f9…

MALICIOUS

PDF

77.7 KB Created: 2021-07-16 02:36:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: b093f4dca532aae90031291b4e8118c9 SHA-1: cbbd7a6a2fb9dd465152a17b3e84b22ab19daa8e SHA-256: c167f794cd57b9f97c2f8d2a1b221bb32f120dcfb6cffedf86533ebadf4a0914
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a link farm pointing to multiple compromised WordPress sites, specifically targeting upload directories within FormCraft and Super Forms plugins. The ML classifier strongly indicated maliciousness, and the presence of numerous links on potentially disposable hosting supports the conclusion that this PDF is designed to redirect users to malicious or phishing content. No scripts were extracted, and the document body was unreadable.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

Heuristics 5

  • 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://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609649cd2e174---2705142791.pdf In PDF document text
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/1a41fa3c979468c06a9433dcfc51b018/3906233196.pdfIn PDF document text
    • https://aokman-drive.com/d/files/ginonarotapaguvinujafafer.pdfIn PDF document text
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c5b2ae684d---50684311246.pdfIn PDF document text
    • https://terminal.hr/userfiles/file/valavurekigi.pdfIn PDF document text
    • http://gtshotel.it/images/file/tupefalovixixax.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16077aa1177252---75037273440.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/e36adfe279e2451f9600e320f5f88052/99816087275.pdfIn PDF document text
    • http://etasystem.net/userfiles/files/gafinujalodenesirisemab.pdfIn PDF document text
    • http://bidwoodmachine.com/d/files/79264414510.pdfIn PDF document text
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/1609147864f085---xogipomupakuzuva.pdfIn PDF document text
    • https://go2germany.ru/files/file/kunefetumetomufu.pdfIn PDF document text
    • https://tolgyesvolgy.hu/userfiles/file/73205629938.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160977e5df0da8---4641955131.pdfIn PDF document text
    • http://videofilm-tv.ru/content/File/zefedi.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087a73e90d05---xaveruliza.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160bbdb78cf519---96600532793.pdfIn PDF document text
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/s30utjki4v42mlc185niv84thi/66778240750.pdfIn PDF document text
    • http://ctyrkolky-gamax.cz/data/dokumenty/jujufuxoxi.pdfIn PDF document text
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085cff8cb14b---kasak.pdfIn PDF document text
    • https://jaiminsales.com/ckfinder/userfiles/files/bazumegunonigiridakow.pdfIn PDF document text
    • http://al-bandak.com/userfiles/file/tidazuboxef.pdfIn PDF document text
    • https://neavocats.com/wp-content/plugins/super-forms/uploads/php/files/b973df5ec3064f27bdf8413b5b2c6454/29498898308.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/5d715a7242a1badb6941a0096a0d1fea/88239393730.pdfIn PDF document text
    • http://innova-perila.ru/upload/files/46954034280.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=graph+of+a+constant+functionPDF 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_off0000cdd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDD9 16672 bytes
SHA-256: 40e62b40bcf9d54741c4b0f32faa1982d18abd768444310d47a2ee6f83e69e8d
font_01_sfnt_off0000f967.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF967 10536 bytes
SHA-256: 0859a5ab95924628e6ccab4b976a0fbcb998455ed07da84dc61cc9a9d65c8dfe
font_02_sfnt_off00011163.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11163 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1