Malicious PDF — malware analysis report

Static analysis result for SHA-256 6d40dcefc0bfc73a…

MALICIOUS

PDF

87.7 KB Created: 2021-09-01 09:52:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: dfbc4cd06f27cbfb70f7647b29b28304 SHA-1: ea085491dcfdb40776bdecfaf6999b25c93aa2cd SHA-256: 6d40dcefc0bfc73a317f4d3b93b8d058315461ebf40ee10d91fc22e0b8280f56
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF sample was flagged as malicious by multiple heuristics and a machine learning classifier, with ClamAV identifying it as Pdf.Phishing.Trojan. The numerous embedded URLs point to compromised CMS upload directories and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The file's structure and the nature of the URLs indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://chcial.ru/uplcv?utm_term=scripture+on+the+crucifixion+of+christ
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160794f3d1d0b3---53704944427.pdf
    • http://velkoobchod-man.eu/ckfinder/userfiles/files/voluzi.pdf
    • http://dragonera.cn/admin/userfiles/file/86599300447.pdf
    • https://twfern.org/upload/ckfinder_temp/files/20210607064716.pdf
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/vnm20cmpi11gqe7s4jm3j14sn2/19663535130.pdf
    • https://sanipro.ma/app/webroot/uploaderfiles/derut.pdf
    • http://gostinica-domodedovo.ru/files/5695936517.pdf
    • http://paulbwatkinslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kosisalujajetovajuw.pdf
    • https://diarch.in/WYSIWYGImage/file/52849218389.pdf
    • https://saunadlaciebie.pl/userfiles/file/minaxifoji.pdf
    • https://prsnashville.com/wp-content/plugins/super-forms/uploads/php/files/65d1424f12a06145f956cad8bad12b93/bimadodebisexizi.pdf
    • https://hanahana.vn/media/ftp/file/30219723669.pdf
    • http://daotaonhaccong.com/uploads/userfiles/file/86361968451.pdf
    • http://www.lbf-cosmetics.com/website/wp-content/plugins/formcraft/file-upload/server/content/files/1608f9e16bb559---sexedewezepabezude.pdf
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/4b4803631339a4dfb13355c13573d74c/5061861677.pdf
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d7d095425ca---65962504601.pdf
    • http://jadeite.ru/images/file/80177821365.pdf
    • https://gute-reise.ru/i/files/files/40418386406.pdf
    • https://cmsschoolkg.org/userfiles/file/texojerojakegufomebasup.pdf
    • https://kocarbon.vn/luutru/files/sidanosiwenolodusuzuwi.pdf
    • http://litho-and-co.fr/ckeditor/upload/files/68562185123.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/g4jk2mmrgkahp2vdsdfcppskq2/8010037011.pdf
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/6669b54da660af936b13801971a5edf8/rixuk.pdf
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/ppbiljnf98dh8jefga70ukfrop/85730496772.pdf
    • https://alianzatours.com/imagenes/file/65609691138.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_off0000f358.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF358 16792 bytes
font_01_sfnt_off00010b6a.bin
3a3404f0525046b136abfef6aee5c02af5f0eb6b6b15fbc4f629b061769beccb
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B6A 17636 bytes
font_02_sfnt_off000138cb.bin
28d656e1f9555fb534a20098b2cd9ce94b6530fff38b95f59d80deeae3a5c2e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x138CB 10648 bytes