Malicious PDF — malware analysis report

Static analysis result for SHA-256 4888af982b1e7211…

MALICIOUS

PDF

83.4 KB Created: 2021-07-02 00:47:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a4b2be650c3431c3248ba3524a37f0c0 SHA-1: 79854900a6c477b08b03185756d8385e37c75d1a SHA-256: 4888af982b1e721101dfcf1fe7c9a51b0dd5f8e402e70d19477c8bff5605224a
156 Risk Score

Malware Insights

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

The PDF file contains a large number of links, many of which point to compromised WordPress sites. This structure is indicative of a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature, classifying it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/1608cb94fbd8aa---xapisunokakok.pdf
    • http://nakatka.com/files/file/nazisan.pdf
    • http://tehnicgaz.eu/files/file/buwuxegivuvak.pdf
    • https://bravo-hk.com/userfiles/file/vezolefereribefufekenamef.pdf
    • http://www.jobsincrete.gr/images/_user_na/file/32994151709.pdf
    • https://taevlingar.se/images/pages/file/sizurorabalodufajeregiji.pdf
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b4c4f509e2d---35959061978.pdf
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/134b7c1ee33870e46d6cc34b5311fbe6/30964819914.pdf
    • http://mlsconsulting.net/cms/files/File/gumidepogeperinozut.pdf
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a882385a23e---nudinododotesejaweda.pdf
    • https://flycam.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607e258f0ff0c---podupexitili.pdf
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/160cb940a323a7---liwomimamixuj.pdf
    • https://autotrans911.com/thread/admin/uploads/file/fufenigibozifeve.pdf
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/aad320454920af7c4fd49c9d0eb175b8/mibikape.pdf
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607f060d242b5---zurokowa.pdf
    • https://lostsoulsmemorialnj.org/wp-content/plugins/super-forms/uploads/php/files/30739e76f650f70b6a283f988b65e774/12583537817.pdf
    • http://moreit.ch/productinfo/file/zudavukobutir.pdf
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/145280420e82e37992e018aa62411f97/49597509615.pdf
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608f425fa6539---wamefekerubad.pdf
    • http://elmiraclassiccountry.com/wp-content/plugins/super-forms/uploads/php/files/vv8o34i1uc3e6h030a0ddrljh1/perevej.pdf
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/227c736225e75bb83560dbc8a8bd4589/71160188604.pdf
    • https://unicon-msk.ru/data/files/soxejakul.pdf
    • https://estigotours.com/wp-content/plugins/super-forms/uploads/php/files/4d18fbcea759666d75f7d4b75d0aa7ea/27089340337.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=c+program+to+find+length+of+string+using+user+defined+function
    • 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_off0000e052.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE052 16792 bytes
font_01_sfnt_off0000f864.bin
c57986fc9b1d8bcce967246e6b83944687b9712b1f3e81f03f8cec142d73d230
pdf-font-stream PDF embedded font (sfnt) at offset 0xF864 17264 bytes
font_02_sfnt_off000125f7.bin
1d67009abb1e6bdac884ca9e8733badadb2bc1ce4d71ed82ccb561a72e073ccb
pdf-font-stream PDF embedded font (sfnt) at offset 0x125F7 11200 bytes