Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a10957529505e5f…

MALICIOUS

PDF

84.8 KB Created: 2021-08-03 21:12:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f76a0315551f12a0d85fa7e8eec9c839 SHA-1: 6b2b99bec567a4ab7ce862e749029ae4171bc3a2 SHA-256: 9a10957529505e5f55a40493b21eb0b8c180e691b5cd13c74294f1a4cfbdffaa
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites utilizing the Formcraft plugin for file uploads. These links likely serve as a link farm to redirect users to malicious content, as indicated by the 'ML_NYX_PDF_MALICIOUS' and 'CLAMAV_DETECTION' heuristics. The presence of multiple distinct hosts and the use of UTM parameters suggest an attempt to obscure the final malicious destination and potentially for SEO-based distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://crewmak.ru/uplcv?utm_term=suma+y+diferencia+de+cubos+ejercicios+resueltos+pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fedbf545db---naxasorofirodetel.pdf
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/16080afe146775---400651550.pdf
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b18d333474---12579776673.pdf
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2f1ad18531---bexelekozizi.pdf
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a694b99beac---4011901167.pdf
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b15f6a9b967---sarakoseluvelobujokojuruf.pdf
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/6b03a562c06fff7d3e88f006c563746a/87928581817.pdf
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607d0f8233000---kupumulugi.pdf
    • http://kodemari.info/data/files/zurijinitelakadujigap.pdf
    • http://hum-lucknow.org/test/fckeditor/file/49856919033.pdf
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/vb7btqqtnn3gl8h1ogs5t4eh06/40644956959.pdf
    • http://aedelsur.com/contenido/files/vunitafazibodotodavebiv.pdf
    • https://anmimar.com/royal/userfiles/file/65609395567.pdf
    • http://thegreenlegacykeepers.com/clients/e/e8/e8dc17949b7ef813e9937e453902477f/File/19585992640.pdf
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d416a3a020---48430830441.pdf
    • http://qhzs88.com/admin/fckeditor_upfiles/file/2021062102191080554.pdf
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/29d46c229a87ddf8de2f5ea33aca3184/dadunebagiteropeporitib.pdf
    • http://www.tecnotrefg.it/wp-content/plugins/formcraft/file-upload/server/content/files/160d2bc6316e74---38589751994.pdf
    • http://dailymaytrogiang.com/userfiles/files/lazuwifosatifazasewazijo.pdf
    • https://jagamimpi.org/contents//files/91747465795.pdf
    • http://gomientrung.vn/uploads/image/files/80074076912.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e097.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE097 16792 bytes
font_01_sfnt_off0000f8a9.bin
d215be737cb8e5631367d8c962d504c29a052915ff7283ef9617349ae07b3b05
pdf-font-stream PDF embedded font (sfnt) at offset 0xF8A9 18664 bytes
font_02_sfnt_off000128e1.bin
480f12dc622602decd5b01d54e940a7b5c58e1913cf4c0d38dafb54e9a36c96f
pdf-font-stream PDF embedded font (sfnt) at offset 0x128E1 11340 bytes