Malicious PDF — malware analysis report

Static analysis result for SHA-256 254cb58de5c1d780…

MALICIOUS

PDF

80.0 KB Created: 2021-09-23 01:57:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5ef17bd86b50d6a4fb7f59e39a970e1c SHA-1: 284c0dd434da12875125512f72aec2c9408d3828 SHA-256: 254cb58de5c1d780d17f1ac7e391fdbc8af50a8347d9942049278888086b9f0d
236 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF file contains multiple links to external resources, many hosted on compromised WordPress sites or disposable domains, suggesting a phishing or malware distribution attempt. The heuristic 'SE_BROWSER_INSTALL_LURE' indicates the document's content directly prompts the user to install a browser extension or update, a common social engineering tactic. ClamAV detection as 'Pdf.Phishing.Trojan' further confirms its malicious nature. The presence of embedded URLs and the overall structure point towards a phishing or downloader attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 8

  • 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 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.
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://ketchas.ru/uplcv?utm_term=block+pop+up+messages+android
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/6fe64758848d66d9a8023876e3bb69db/36097651161.pdf
    • http://studiolegalezullo.eu/userfiles/files/48385645190.pdf
    • http://makrostal.pl/user_images/file/73705413521.pdf
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613595851de2d---99813756226.pdf
    • http://ambulatorioveterinariopisillibertozzi.eu/userfiles/files/56327517429.pdf
    • https://ofcourselc.com/admin/uploadsfile/moxepiveworoxavobetoduris.pdf
    • http://ndt-ultratech.com/files/22305751531.pdf
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/40aa80d504e4ecfe8378fbc2a558e065/temenawuxanavasiso.pdf
    • https://dalycity.com/wysiwygfiles/file/dunovexugide.pdf
    • http://pacemakerpressintl.com/uploads/assets/file/rowux.pdf
    • http://futuralagoparking.eu/userfiles/files/paxuposedizegukepopo.pdf
    • http://italiangreyhound.pl/img1/userfiles/file/51332931565.pdf
    • http://agrocare.hu/ckfinder/userfiles/files/49076795241.pdf
    • https://baruipur.org/ckfinder/userfiles/files/25985764314.pdf
    • https://chowdhurytourism.com/ckfinder/userfiles/files/55857140601.pdf
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/96af834d1b61eedf6236d61f2b8bf586/87629278015.pdf
    • http://foreverymuslim.net/home1/forevev3/public_html/foreverymuslim/upload/file/buvodokelepuban.pdf
    • http://dailygameresult.com/editor/UserFiles2/files/74926691586.pdf
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161421d7a0cf3e---fatebi.pdf
    • http://ideal-site.ru/userfiles/file/damopekuxudarixegel.pdf
    • http://namadagaskare.ru/ckfinder/userfiles/files/gegazotepubelemota.pdf
    • http://xn----7sbbgprpk7biiq.xn--p1ai/admin/ckfinder/userfiles/files/85231660956.pdf
    • http://qbcar.ru/ckfinder/userfiles/files/32202614836.pdf
    • http://channelletterguide.com/ckfinder/userfiles/files/4659756946.pdf
    • http://llux.vn/uploads/files/dedeku.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_off0000d341.bin
71e172b2d348ce8e46cfbec71114e8848b49c06e034233cbd1ac5ff09d75be3e
pdf-font-stream PDF embedded font (sfnt) at offset 0xD341 11004 bytes
font_01_sfnt_off0000ec98.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC98 16792 bytes
font_02_sfnt_off000104aa.bin
2ce566ece188d9fd39e48e280f9c379ece6fa1ac8d48182bfe308feeb6dd7616
pdf-font-stream PDF embedded font (sfnt) at offset 0x104AA 17856 bytes