Malicious PDF — malware analysis report

Static analysis result for SHA-256 505f85fa19a4e93a…

MALICIOUS

PDF

70.6 KB Created: 2021-09-24 17:52:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 184b982b0e4319ab12be22d6a00d9730 SHA-1: 1ed2884ef0245f3c4ca1442ceccdac9fd417297f SHA-256: 505f85fa19a4e93a5a2b3c759a5644acfe302e8876f3c427ec2ab9b2a58b8450
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some of which are hosted on compromised CMS uploads or disposable domains. The document body is heavily obfuscated and unreadable, providing no direct content clues, but the overall structure and heuristic firings strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9954

Heuristics 6

  • 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 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://msiutilities.net/documents/fivujegaxodono.pdf In PDF document text
    • http://www.prodomasa.com/ckfinder/userfiles/files/22006326457.pdfIn PDF document text
    • https://ourcampuswindow.com/ckfinder/userfiles/files/14845069030.pdfIn PDF document text
    • http://uhorder.com/upload/files/tokolamonapukugakalujomu.pdfIn PDF document text
    • http://digifast.cz/userfiles/suxumudisifepe.pdfIn PDF document text
    • https://red-adlay.com/upload/files/zurud.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/53555304594.pdfIn PDF document text
    • http://dxczx.com/ckfinder/userfiles/files/20210924_191228.pdfIn PDF document text
    • http://wx-bm.cn/upload/ckimg/files/202109200106344194.pdfIn PDF document text
    • http://topenglish.sk/app/webroot/gallery/files/kigajateduzavor.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bd3e3adb21---xajivifolukakutixu.pdfIn PDF document text
    • http://szhlfz.net/upload/varenezamexudubebubizun.pdfIn PDF document text
    • https://rowsontw.com/shopadmin/upload/files/tunakariwagulizugalopus.pdfIn PDF document text
    • https://wodepcb.cn/uploadfiles/files/95224035715.pdfIn PDF document text
    • http://ambvetbrashersclavoghisu.eu/userfiles/files/kujeselova.pdfIn PDF document text
    • https://www.premiumtrade.ro/ckfinder/userfiles/files/21901020429.pdfIn PDF document text
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/da87052be0e18b32b906e0ec63b5da9a/kovepupowemenoku.pdfIn PDF document text
    • http://seattleteriyaki3.com/uploads/files/wurezifavofid.pdfIn PDF document text
    • https://bikidi.com/UpFiles/WebEditorFiles/file/pudewukudonu.pdfIn PDF document text
    • https://member-amz-seller-system.de/wp-content/plugins/super-forms/uploads/php/files/204fcf50c2b6b3ea24da0c4684720ca2/76170310387.pdfIn PDF document text
    • https://inverpalmas.com/aym_image/files/56817432375.pdfIn PDF document text
    • https://tylbm.com/Upload/ckeditor/files/59680059030.pdfIn PDF document text
    • http://luxcottage.ru/stroykamen/userfiles/file/tasalaz.pdfIn PDF document text
    • https://certifiedcollisionrepair.com/home/cert/public_html/ckfinder/userfiles/files/xokexijuduviborafiwiteb.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=3d+gun+addon+minecraft+pePDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000afb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFB4 16860 bytes
SHA-256: b9bf3ab724e3eb2a44fbc2cb5f072e356b251188b1ac03664143d04612c6baf2
font_01_sfnt_off0000db29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB29 10924 bytes
SHA-256: 6ec7851c9f03154af32f96b7d8740eac23063920037dd8e616d9337c1eb8b0fe
font_02_sfnt_off0000f43c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF43C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1