Malicious PDF — malware analysis report

Static analysis result for SHA-256 4906604cb17fa36c…

MALICIOUS

PDF

82.7 KB Created: 2021-09-17 16:48:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: acfaf8474275ca64118063e1728f6879 SHA-1: 03ef4bcec94b288fea645c8f6cc09ab7a1ce45fd SHA-256: 4906604cb17fa36ce81b066a32a04f4f9fea3c4aa5bf7b40ef8a4a2f24347704
156 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to malicious sites for phishing or further exploitation. The presence of numerous links on potentially compromised CMS upload directories suggests an attempt to disguise malicious content as legitimate files.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://evaemlak.com/userfiles/file///meram.pdf In PDF document text
    • https://digireg.cz/upload/jekunosobi.pdfIn PDF document text
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/ecb6bc71b6193a67f813594710387cfd/29480316849.pdfIn PDF document text
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/1d24f916e7b4f4672fba18a04b7b2795/miruxapolabafisin.pdfIn PDF document text
    • http://nollve.com/img/editor/image/file/5468467544.pdfIn PDF document text
    • https://datenglagi.com/contents/files/43740103767.pdfIn PDF document text
    • http://joyandwowbook.com/upload/file/tiraridagafufo.pdfIn PDF document text
    • http://sireny.net/share/files/16952314445.pdfIn PDF document text
    • https://loffoxfitness.mvwebsolution.com/userfiles/files/fevizuwureteraratijo.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613d4a1380de9---risozuravejeruwatirorejok.pdfIn PDF document text
    • http://loadcell.vn/Images_upload/files/75464476652.pdfIn PDF document text
    • http://art-lan.ru/uploads/assets/file/matojegele.pdfIn PDF document text
    • http://kulturazebrak.cz/userfiles/18730661301.pdfIn PDF document text
    • https://kga-am-adlergestell-ev.de/kga/ckfinder/userfiles/files/58207261013.pdfIn PDF document text
    • https://heuresromantiques.com/upload/files/jiwimewiwo.pdfIn PDF document text
    • http://fongyoskert.hu/userfiles/files/bodoxisotivunun.pdfIn PDF document text
    • http://wienbildarchiv.com/upload_files/files/97099783710.pdfIn PDF document text
    • https://eltonltd.ru/sites/default/files/uploads/zakulibi.pdfIn PDF document text
    • http://satunatc.ac.th/ckfinder/userfiles/files/36151686792.pdfIn PDF document text
    • https://empresa-venta.hr/files/11343951517.pdfIn PDF document text
    • http://www.og2c.com/images/file/5178759018.pdfIn PDF document text
    • https://m-astar.com/UserFiles/files/larejumujowelaraxiwup.pdfIn PDF document text
    • http://hotel-ambassador-nice.com/upload/files/63808918767.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=streaming+justice+league+zackPDF 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_off0000de6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE6C 10912 bytes
SHA-256: d2e0a3fcf7da5b04dff304513e9f7897eb7e170dedeb362253bfc92f2339b2f7
font_01_sfnt_off0000f7a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7A6 17624 bytes
SHA-256: d4905032b8028144a4629c77818220e5a9c8a9ebff5a64620b688f99b42a02cb
font_02_sfnt_off0001251e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1251E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1