Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ecc737f54af7c6c…

MALICIOUS

PDF

76.7 KB Created: 2021-09-19 06:04:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a0a764bbbcee58770caa8a0d2ce66638 SHA-1: 34d94414dc8f1c51f2e5729f02c31dfa55047e28 SHA-256: 8ecc737f54af7c6c9d9c01bb3951e7346fac4dd0e3a97bdf6761807291c6aacf
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://crysiq.ru/uplcv?utm_term=ppsspp+cso+roms
    • http://tantos.jp/js/upload/files/9717044748.pdf
    • http://merklink.nl/site/data/ws/files/40111095760.pdf
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133d690481ec---63312038303.pdf
    • http://mxag.com/upload/browse/file/butujilenuzemibukimaduv.pdf
    • http://elfuklid.cz/foto/Image/file/lasokewagimudile.pdf
    • https://nikoljski.com/ckfinder/userfiles/files/84535060802.pdf
    • http://www.masozilina.sk/ckfinder/userfiles/files/21125247339.pdf
    • https://www.edmcenter.xyz/ckfinder/userfiles/files/jigilavumagusiralubifefun.pdf
    • http://portofmiamitunnel.com/system/js/back/ckfinder/userfiles/files/reroradiwejoxawinesotafar.pdf
    • https://inprovitcentroamerica.com/ckfinder/userfiles/files/17958433867.pdf
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134387934968---kexubena.pdf
    • http://xaydunghoangthanh.com/img_duhoc/files/36790340281.pdf
    • http://scamps.biz/userfiles/file/zebugulofugusulinikel.pdf
    • http://runbo.net/upfiles/files/16306267566123.pdf
    • http://motovelo-nmsk.ru/userfiles/file/vipupozukegiwijare.pdf
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/7ea596ad730538c3d853506e0f7c3b9f/wubanudoj.pdf
    • http://peetersinstallatietechniek.nl/upload/files/ruranowutikefalel.pdf
    • https://csom.cz/wp-content/plugins/super-forms/uploads/php/files/486b3a783ee5fc542c5d919dae014fa3/kavirigireki.pdf
    • https://www.gurgy.net/ckfinder/userfiles/files/lagaxavojupisaratudezozu.pdf
    • http://tehnicgaz.eu/files/file/zapajaboru.pdf
    • https://ultralloy.net/upload/files/fuvadezotola.pdf
    • http://sitarofindiamd.com/userfiles/file/83167350137.pdf
    • http://dpnovelty.com/upload/files/81337799155.pdf
    • http://olympiad-bigben.ru/ckfinder/userfiles/files/tumadoniperanifed.pdf
    • https://tcremich.lu/files/files/xiribup.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_off0000c669.bin
09ae723786ea0e4748f030a268202892726132bad1a8acc67cf2a4bb5a161bcf
pdf-font-stream PDF embedded font (sfnt) at offset 0xC669 19316 bytes
font_01_sfnt_off0000f7fb.bin
2402d64f0863316241085aabe1cf729a65c4de6fa700a3bc1f0d3ad8555e0751
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7FB 9900 bytes
font_02_sfnt_off00010dce.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10DCE 16792 bytes