Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d6e53f20edc9aac…

MALICIOUS

PDF

94.4 KB Created: 2021-08-31 03:06:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 4e8a3b85532e6911282952fc2fe041dd SHA-1: cac777e175aad817d718b555a9b21d1224dad846 SHA-256: 8d6e53f20edc9aaca885acb523397990bfb0a185ddab828809728399f6071a67
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file detected by ClamAV as a phishing trojan. It contains embedded JavaScript, which is a common technique for executing malicious code within PDFs. The file also includes numerous external URLs, some of which point to compromised CMS upload storage, suggesting an attempt to redirect the user to malicious sites. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://pixomot.ru/uplcv?utm_term=prove+that+2+is+an+irrational+number PDF link annotation
    • https://transpack-krumbach.de/_upload_bilder/_filemanager/file/5954806910.pdfIn PDF document text
    • https://conexus-study-abroad-travel.com/ckfinder/userfiles/file/62937853250.pdfIn PDF document text
    • http://natur-pet.cz/webpagebuilder/ckfinder/userfiles/files/8070641163.pdfIn PDF document text
    • https://bikeid.net/ckfinder/userfiles/files/ratusazekifuvaxizazu.pdfIn PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/kmti0pdevn73us7pmq1dsrct47/4157967963.pdfIn PDF document text
    • http://vasekurzy.cz/userfiles/file/45881306578.pdfIn PDF document text
    • http://turnwealthy.com/ckfinder/userfiles/files/72284190544.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160962e7f653a1---gelepovagilezujuzas.pdfIn PDF document text
    • http://poetische-malerei.de/web/editor/files/kiseduxekagagidovaxagut.pdfIn PDF document text
    • https://charqueadaboavista.com.br/wp-content/plugins/super-forms/uploads/php/files/7efdbe081bd5aa1f3c62c298084f65d4/40853704382.pdfIn PDF document text
    • http://appinaris.net/ckfinder/userfiles/publics/files/zaseranizenama.pdfIn PDF document text
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/krij0h5bvmlas98e4cdr1vd2n2/33900799873.pdfIn PDF document text
    • https://mamo-tato.ro/userfiles/file/76514582211.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc62ae9227---56024730077.pdfIn PDF document text
    • http://angelojrobles.com/admin_initial_test/userfiles/file/92549876197.pdfIn PDF document text
    • https://yingzhaoliuart.com/upload/file/2798527954.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/tmdsh6u9msm93fgdhuf1qkhnav/53423121216.pdfIn PDF document text
    • http://crystaltrade.hu/data/file/lonum.pdfIn PDF document text
    • http://kemenyseprosiklos.hu/upload/file/varixorujab.pdfIn PDF document text
    • http://www.artefuoricentro.it/js/lib/ckfinder/userfiles/files/54837339304.pdfIn PDF document text
    • https://vinisfarm.com/wp-content/plugins/super-forms/uploads/php/files/c4b50207b226c08c86d49b47811b8f8b/62393999.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/16095e9a91743d---86122816321.pdfIn PDF document text
    • http://lica-mpt.it/userfiles/files/kogobogisoviledebebe.pdfIn PDF document text
    • 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_off000102c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102C7 10800 bytes
SHA-256: 22ae9bd93454b71b2acef44ca60fe7687f092e4dd94bf7a535e9047e28cddecd
font_01_sfnt_off00011b8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B8B 20488 bytes
SHA-256: 2459816dff01908f189099c950f4a844a2cd52f32adcc46287fd65d6b58c40dc
font_02_sfnt_off00015148.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15148 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1