Malicious PDF — malware analysis report

Static analysis result for SHA-256 55938f45a80d4ad4…

MALICIOUS

PDF

80.9 KB Created: 2021-09-18 10:44:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 73da4b22efd9f61584da44e65a0b75a0 SHA-1: 64ff658e608f9aacfe37c58b6224232903ab7230 SHA-256: 55938f45a80d4ad4cbd4fa65dbd989dd056293bae5431601873cc7dcc962c1f5
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan. It contains numerous external URIs and is identified as a link farm, with several URLs pointing to compromised or disposable hosting. Embedded JavaScript was also detected, suggesting potential malicious scripting capabilities within the PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 7

  • 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.
  • 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://wastran.ru/uplcv?utm_term=clash+of+clans+apk+ultima+version
    • http://autoset66.ru/admin/ckfinder/userfiles/files/54185678911.pdf
    • https://forumhrdbekasi.com/webroot/userfiles/files/guzavelasutefigij.pdf
    • https://istanajpdua.com/contents/files/fokelorapaviparunaz.pdf
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134cd66d9977---jidopijir.pdf
    • http://residencecarlofelice.com/userfiles/files/boxovonaworaze.pdf
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/07f385c12d025bbc37067b765939bc04/71674050822.pdf
    • https://maritime-models.com/userfiles/file/raniwuxemi.pdf
    • http://consorzio-csa.it/userfiles/files/3527412296.pdf
    • http://tubesealer.com/uploaded/file/134870894461435d0993b19.pdf
    • http://darec.sk/files/files/21611439982.pdf
    • https://gestionarival.com/userfiles/file/34553505866.pdf
    • http://classiccar-jp.com/js/upload/files/59565101251.pdf
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132f7f5b011a---81876652050.pdf
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/0jvnf99aka14dcg98v1cdifp76/98994432143.pdf
    • http://bestbuyfromindia.com/userfiles/file/33269589563.pdf
    • http://sasnowosielski.com/ckfinder/userfiles/files/xugamuv.pdf
    • https://khachsan295doson.vn/namthuan/images/news/files/tafipetax.pdf
    • https://yumasri.com/assets/ckfinder/userfiles/files/jeresadagovuzonamotitisat.pdf
    • https://preciseenergygroup.com/media/rovab.pdf
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16131aad22527e---50664068645.pdf
    • http://restauraceeverest.cz/userfiles/file/51478472115.pdf
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/40728430177.pdf
    • https://linker.tw/files/79346722001.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_off0000d5d9.bin
8597348d0bd22eefea28dd6dc6e848c7cd02c3f7429868b3d9fdcf66e3af96e6
pdf-font-stream PDF embedded font (sfnt) at offset 0xD5D9 17968 bytes
font_01_sfnt_off00010474.bin
afc5758498d2d211b5b52d59fe723749678c824a1dad489fc5ccb1215b939038
pdf-font-stream PDF embedded font (sfnt) at offset 0x10474 11036 bytes
font_02_sfnt_off00011e00.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E00 16792 bytes