Malicious PDF — malware analysis report

Static analysis result for SHA-256 77b707d8023c9c28…

MALICIOUS

PDF

84.5 KB Created: 2021-07-07 07:45:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1f1d3db81b16c9ecdc9d88945f93d51a SHA-1: 8f19104d47a414fdf96a37c1162c481b35997672 SHA-256: 77b707d8023c9c28b29fd1b6948d4a521d3349f5c5d0b0c7e78f3eb67988223f
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to compromised WordPress upload storage and other disposable hosting sites. These links are likely used for phishing or to serve further malicious content.

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://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160ac0b80b337c---24485217174.pdf
    • http://longearedhounds.com/clients/65743/File/rawevorupo.pdf
    • https://amrapalispot.com/userfiles/file/68243641507.pdf
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/160c05e0172c73---88738715851.pdf
    • http://latexindia.com/userfiles/file/nepididekuba.pdf
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/160c4f86330f8d---11185619505.pdf
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/696b8bdedfb74730e0dee6ecb5b1b87a/29314922040.pdf
    • https://autotrilogy.com/wp-content/plugins/super-forms/uploads/php/files/1f35e2c294162d71da98244cdae784d1/fakigipexoxo.pdf
    • https://mt-creativestudio.com/ckfinder/userfiles/files/fefamufuterovezegoduk.pdf
    • http://esipro.lu/userfiles/file/47946332497.pdf
    • http://chunmianxian.com/upfolder/e/files/20210704003359.pdf
    • https://biorenta.lt/ckfinder/userfiles/files/zanulawuzigowapovakodudik.pdf
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/1609193f6164de---gagexef.pdf
    • https://www.autodepotperformancegroup.ca/wp-content/plugins/super-forms/uploads/php/files/26fug2uuit61p3org1kg9mcund/xekapupif.pdf
    • http://epoxidice.ro/mm/file/visux.pdf
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5196754058---80239865817.pdf
    • http://www.advokat.com/app/webroot/img/fck/file/vitujuwalato.pdf
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/fad74d80528f6c03073dbb0cfd381876/bizupaja.pdf
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/402d5bd47fc815d495a8f41dcc586b16/xukovopalabofagowo.pdf
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/a024bde2cc9bf7ac5a08679ddd9583d5/wikekofaxubajuxiforoxo.pdf
    • http://st03.it/userfiles/files/vivazitamepowagegesegupil.pdf
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/eabe4fd1e65913c48b36633f86e92736/35163090887.pdf
    • http://apexibd.com/uploads/fck_uploads/file/laxadefimewubixuwami.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=gilmore+girls+a+year+in+the+life+summer
    • 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_off0000e8e8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE8E8 16792 bytes
font_01_sfnt_off000100ff.bin
92f741b7297d0fa0e423468b5864ba80edeb463d54088a73d714f6e0626bcad3
pdf-font-stream PDF embedded font (sfnt) at offset 0x100FF 10916 bytes
font_02_sfnt_off00011a15.bin
61e08274eff887923ebe7a561066360750945026fbdd45228b6e7f35456ffc35
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A15 16328 bytes