Malicious PDF — malware analysis report

Static analysis result for SHA-256 2a55819439277eb5…

MALICIOUS

PDF

82.3 KB Created: 2021-09-06 22:02:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d66ad2b5ba887bddbabcb112c6d5c488 SHA-1: d6a99440f15a5b8ce97c7734e1e9dd0fdbdfc25c SHA-256: 2a55819439277eb551afd045156ca499adcd270080aa4758f577ca9edb19c296
164 Risk Score

Malware Insights

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

The PDF contains numerous links to compromised websites, indicating a phishing or malware distribution attempt. The presence of a 'download button' lure further supports this, suggesting the file is intended to trick users into downloading malicious content. ClamAV detection and ML classification confirm the malicious nature of the PDF.

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 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://hkbca.org/UploadFiles/file/20210813054755177.pdf
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/cu83tg1f0t7i7ev5m4c6df3fjb/76075415797.pdf
    • http://scottsdalehighbeavers1978.com/clients/80197/File/wetoxe.pdf
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606f548da4727---xomukoduxani.pdf
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/ses2n4nvbtkrvjebqc5r78c2cu/60228998870.pdf
    • https://cvenhancer.com/wp-content/plugins/super-forms/uploads/php/files/78c8ecb1f9043ae9b62fa830c76d70f7/7667545573.pdf
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/fc9155d5897477597ade945c016110fc/baxelitoxavidenunu.pdf
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608422b322929---rixabexamapiw.pdf
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16086c02e28aa8---boruj.pdf
    • http://maketmaster.ru/admin/ckfinder/userfiles/files/gikudokizepawavuv.pdf
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160bf66979e92d---6165286379.pdf
    • http://www.cpnatacao.pt/backoffice/ckfinder/userfiles/files/puzigubelosoxox.pdf
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b0d5719a3b---lonibirajanor.pdf
    • https://medtek.vn/storage/file/29951262230.pdf
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/1607f6bca03cf8---51813493391.pdf
    • http://vivo-mebel.ru/upload/file/75390847140.pdf
    • https://feniks9.ru/ckfinder/userfiles/files/xutadi.pdf
    • http://tvtamminhphat.com/uploads/userfiles/file/58013503875.pdf
    • http://instalace-charvat.cz/userfiles/file/37004111816.pdf
    • http://renknh.com/ckupload/files/95865778264.pdf
    • http://noahmission.org/dataroom/file/sasegozakemufejuzuwoneja.pdf
    • https://grahampropertytax.com/wp-content/plugins/super-forms/uploads/php/files/57a00e4d14c59d79700a61e2edcd4a2e/79569749995.pdf
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/16090d71fd0165---3903486080.pdf
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607fa3888ecbd---jamorowesogif.pdf
    • http://www.ecvbrass.ch/user/web/file/46247027182.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=uhf+reader+zkteco+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_off0000da86.bin
c013a3fe95831492c5307d0d3d945e4b622c0b454415f7545156beac70cd7654
pdf-font-stream PDF embedded font (sfnt) at offset 0xDA86 18912 bytes
font_01_sfnt_off00010b5c.bin
8ca0522cd07e8adba851bd1bc55ec329e9d4b4f11a3c8718c9418f7d65297028
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B5C 10464 bytes
font_02_sfnt_off0001234e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1234E 16792 bytes