Malicious PDF — malware analysis report

Static analysis result for SHA-256 544f41f6ae826922…

MALICIOUS

PDF

78.6 KB Created: 2021-09-04 05:25:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b6590764c8d54cb98bd17606d058d181 SHA-1: 2374259ce2e3516bb45fb1f218d54a906b28685f SHA-256: 544f41f6ae826922559f8afa5d1afd0a9c8b277e34080cca402922ab87c012e2
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple potentially compromised or disposable domains. The presence of numerous unknown URLs suggests an attempt to distribute or redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/1de1bac93734692c6e2cef88e354fa14/ninunukeko.pdf In PDF document text
    • http://xn--franzsischebulldoggen-lec.eu/userfiles/file/85712216875.pdfIn PDF document text
    • http://best-infosystems.com/userfiles/file/regisogopakugewikam.pdfIn PDF document text
    • https://visionbrindes.com/admin/fckeditor/userfiles/file/saxesabojeg.pdfIn PDF document text
    • https://triangle-electronics.com/assets/userfiles/file/folepokidefepuvoxepe.pdfIn PDF document text
    • http://abwingssuffolk2.com/uploads/files/36353311171.pdfIn PDF document text
    • http://sethhukumchandschool.com/userfiles/file/kozubowebapexa.pdfIn PDF document text
    • https://vietnaminsight.biz/ckfinder/userfiles/files/44028248660.pdfIn PDF document text
    • http://mistral-paints.cz/userfiles/files/fokesizexep.pdfIn PDF document text
    • http://nadiadsa.org/userfiles/file/46541509036.pdfIn PDF document text
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608167387b01b---liwigesavimemokazuguleb.pdfIn PDF document text
    • http://theettiaresmontreal.com/clients/f/f0/f03dfc1790708d0b03c48e9879ef2ea6/File/28803591036.pdfIn PDF document text
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/85876cb3b3669e66558b92b2c39da984/72433638933.pdfIn PDF document text
    • https://haruhonpo.com/upload/haruhonpo/files/83861588263.pdfIn PDF document text
    • http://ashioke.com/images/library/File/65158687308.pdfIn PDF document text
    • http://bettaletroom.com/file_media/file_image/file/34693858566.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/e3840ac17d8b77971f98776063d320d3/9492158210.pdfIn PDF document text
    • http://udmvdpo.ru/images/files/jiwovibodasogojugojob.pdfIn PDF document text
    • https://damsindia.org/admin/uploads/file/24648223050.pdfIn PDF document text
    • http://brandnewgoods.net/userfiles/file/fufatipiresotunokiwosu.pdfIn PDF document text
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/83fc3851612f7c039112d7b52dfcc6c5/dofezow.pdfIn PDF document text
    • https://laughteronlineuniversity.com/images/upload/files/vejivubuzewo.pdfIn PDF document text
    • http://longarmquiltacademy.com/fckeditor/userfiles/file/modelas.pdfIn PDF document text
    • http://printific.com/images/contentimages/files/zonusekivukixifokukonufaz.pdfIn PDF document text
    • https://myupfield.link/wp-content/plugins/super-forms/uploads/php/files/k2k8mgi8c7nu6rjbjk72mkc37j/kuwosatogivifevexiperal.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=convert+word+to+pdf+online+free+zamzarPDF 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_off0000cf5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF5A 10736 bytes
SHA-256: 3befe4959afdf3f0d6af2510578c2a6c6e1861f2aeb6d92e645c2f3d75b75bd8
font_01_sfnt_off0000e819.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE819 17280 bytes
SHA-256: 8c1de4f7788c08d47383f44be724323df369b759ad334a90501941e83f2eba43
font_02_sfnt_off000114b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114B6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1