Malicious PDF — malware analysis report

Static analysis result for SHA-256 9522efb447219783…

MALICIOUS

PDF

79.3 KB Created: 2021-09-04 10:06:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4978b9e65a2e93dec713b034e0c5c3cf SHA-1: 779d13e1a5f8b5a8fd0b325af7a52d0de7fc38bf SHA-256: 9522efb447219783b2df23be00cd2e3c6da0b72ce4683d7c79e50ddd27f6fe19
164 Risk Score

Malware Insights

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

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to numerous URLs hosted on compromised or disposable domains, likely to facilitate the download of further malicious payloads. The presence of a 'download button' heuristic further supports the lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://krisoc.ru/uplcv?utm_term=curriculum+design+volume+one+pdf
    • http://massimomoroni.it/userfiles/files/38806762655.pdf
    • https://gimenezricarte-deltabogados.com/ckfinder/userfiles/files/65264058112.pdf
    • http://kamennykoberec.eu/editor_uploads/system/files/regonilafuniwuxaj.pdf
    • http://perlawarmii.pl/userfiles/file/76685047703.pdf
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086788952d2e---wivevubakidob.pdf
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8de092ce6b---8686926811.pdf
    • http://51www.org/uploadfile/file/3f5346a098af072905031ff07223c641.pdf
    • https://bnbtravels.com/ckfinder/userfiles/files/bedegupusesurivetazijow.pdf
    • https://www.dolphinrfid.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d653af12bd6---35914514246.pdf
    • https://palcev.ru/userfiles/file/55261382857.pdf
    • http://leaguengn.com/userfiles/file///68689514956.pdf
    • http://angelescare.com/userfiles/file/xipunarunomawenatava.pdf
    • https://anthonygillant.com/userfiles/file/19305483791.pdf
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b0ce1dbecce---janaruma.pdf
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608199930e3e8---vorikuzitawesogisu.pdf
    • http://dahchen.tw/userfiles/files/keramed.pdf
    • https://bikeid.net/ckfinder/userfiles/files/wagivaligediwisito.pdf
    • http://morard-mcf.fr/data/Files/64565554278.pdf
    • http://envigest.cz/upload/file/zigodulatexav.pdf
    • https://33mobility.net/uploads/files/35813990032.pdf
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a56b4433527---xatat.pdf
    • https://gilbertems.com/videos/file/38646124222.pdf
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082ddb0813ed---zuvazijifujomenatafi.pdf
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/0jv48b8c1u39su76394b9uss9t/95495800513.pdf
    • https://alexandrapanayotou.com/web/images/static/file/ponuruvinefobaxula.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_off0000d13c.bin
39cb960d5b330e065a0aee07437749f2a15a1ba35ecc75be9c6e74e0a5531c48
pdf-font-stream PDF embedded font (sfnt) at offset 0xD13C 17664 bytes
font_01_sfnt_off0000fea7.bin
dbb57c5f7c87073db9ed55bb20b3b9669236d9c0f56e280e09a63fbed806efcd
pdf-font-stream PDF embedded font (sfnt) at offset 0xFEA7 10900 bytes
font_02_sfnt_off000117a9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x117A9 16792 bytes