Malicious PDF — malware analysis report

Static analysis result for SHA-256 b21726945dc88b71…

MALICIOUS

PDF

83.7 KB Created: 2021-06-26 05:23:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: bc197fcfcf8c797e14dfdf8e2e982324 SHA-1: a045fe71198ad7f915a580eee151018596c8ec46 SHA-256: b21726945dc88b71fb8ec3ff217bb67a9d405c41f2642d98cce21cdde45911eb
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://namngonviet.vn/user-/files/3869165343.pdf
    • http://asiavent.com/UserFiles/file///36501898118.pdf
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ce24d1bdf2b---8709584754.pdf
    • http://fritz-fahrlaender.ch/download/gujewufokexanewesitenopar.pdf
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092ce0c82c9a---tejosalumofamanile.pdf
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d42efc7bcf---bemosoxogol.pdf
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/g8ctii8msv33kvs9655ia959kb/dubedufakerer.pdf
    • https://gastrotest.co/ckfinder/userfiles/files/wogavubifuse.pdf
    • https://yourlightingbrand.com/wp-content/plugins/super-forms/uploads/php/files/3357e04cfecda5650a3f1e94a3231fd2/83587374577.pdf
    • http://autoshiftbid.com/fckeditor/userfiles/file/41992141349.pdf
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/160898d9ab9c5c---74880816055.pdf
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608663e6786ce---fipigekogimufojefi.pdf
    • https://tolgyesvolgy.hu/userfiles/file/89026838185.pdf
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6a129369c5---19628454968.pdf
    • http://mvdeastudio.it/userfiles/files/91661006150.pdf
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/3fbcf870315f48475c2c8594c9c30446/24459978907.pdf
    • http://kolesnikov.pro/ckfinder/userfiles/files/37283808818.pdf
    • https://stratasphere.online/userfiles/file/39203808823.pdf
    • https://raiporjai.com/piceditor/file/7395388196.pdf
    • https://bataretak.com/img/files/file/potiwuxitekonavonegat.pdf
    • http://bahtiyardishekimi.com/fckfiles/file/70694091192.pdf
    • http://highendschmiede.de/highendfiles/file/vipaxujinalokikigenodifo.pdf
    • http://sztarmedia.hu/_user/file/rufejexitapobelofudodibez.pdf
    • http://aliglobshop.com/userfiles/file/subisigigevijene.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=how+to+find+archived+messages+on+messenger+on+android
    • 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_off0000e2ca.bin
35dbf82f90b11fed428273af97b1b434febc32847bdde562b249d7c8df3fb944
pdf-font-stream PDF embedded font (sfnt) at offset 0xE2CA 17176 bytes
font_01_sfnt_off00010f6c.bin
4dbfb259267e768e0fb9d0155586a3517a1892a70e6a36c205f7fc030824abb8
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F6C 11020 bytes
font_02_sfnt_off000128b5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x128B5 16792 bytes