Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc4e6823852bf2f4…

MALICIOUS

PDF

73.4 KB Created: 2021-07-08 07:51:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 4020c37b2b97189447e3020851695839 SHA-1: 949274c328180ef9efab7ba46ee65cdcfb54dd10 SHA-256: dc4e6823852bf2f49fb94ff73104a94228124c2307bc5ad43fe596e78b7ed508
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to compromised WordPress sites and other domains, likely to host or redirect to malicious content. The presence of multiple distinct hosts and the use of 'utm_term' parameters suggest an attempt to obscure the final destination and potentially engage in phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

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://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/cc7d552c2fc850a1f4a82e5532055a9a/mitakupinadamirivo.pdf In PDF document text
    • https://bdblue.com/ckfinder/userfiles/files/vekanirudajebise.pdfIn PDF document text
    • http://eko-inwest.eu/upload/file/tevus.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/9223668394.pdfIn PDF document text
    • https://nikoljski.com/ckfinder/userfiles/files/malikonirisomize.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a95b668595---fezadis.pdfIn PDF document text
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160acf1cd7bd46---zaxefubukitafumikonope.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608033745fd82---6060613367.pdfIn PDF document text
    • http://biometria.pl/photos_fck/file/68808695681.pdfIn PDF document text
    • https://traonguoc.vn/wp-content/plugins/super-forms/uploads/php/files/b37ouu1eb1l23v90lhdeslogd9/40591775909.pdfIn PDF document text
    • https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/af3d4ae7ff9cbff6fd49b331e316fd20/mexidez.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608ded7349445---sopegeva.pdfIn PDF document text
    • https://precisionautoandac.com/wp-content/plugins/super-forms/uploads/php/files/dfae2b20d9232262e0234367edd080a2/poromobarimiwurita.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7bad884f4d---8577539466.pdfIn PDF document text
    • https://juniorclublivorno.com/sitonews/images_upload/files/24148565537.pdfIn PDF document text
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/c6385c4e9fff6b49ccff52c53ed533f5/66692539263.pdfIn PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160df9946f3c6b---lesivanegiton.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/160cbbdaeef899---3819714980.pdfIn PDF document text
    • http://bosch-service-center.ru/uploads/files/vulisolafa.pdfIn PDF document text
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b8b5be51915---24453807814.pdfIn PDF document text
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/679532b94c0a10117e9f736f6726ee85/97717026895.pdfIn PDF document text
    • https://mvpartners.be/images/uploadedimages/file/bewepop.pdfIn PDF document text
    • http://ipmarketing.net/userfiles/file/94452585705.pdfIn PDF document text
    • https://autotrilogy.com/wp-content/plugins/super-forms/uploads/php/files/ab245c1b8881de3b1b0fccadf667672c/papubezukimi.pdfIn PDF document text
    • http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160822a5b67cf9---zuzivigegelonosarid.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c498ee1e8ff---sebesexizi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=may+i+request+you+to+please+sendPDF 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_off0000bf15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF15 10736 bytes
SHA-256: 4314419689424d36e56c497000deacc2c641f9b88b0397dff6f9f1b490affb5f
font_01_sfnt_off0000d7ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7AD 15568 bytes
SHA-256: 3926f1de65d4cbf376fd2a48eb15aa026d5468dd2dfa1cd6ae0d2b037e69ac99
font_02_sfnt_off0000ffe3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFE3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1