Malicious PDF — malware analysis report

Static analysis result for SHA-256 56ab73b25a6547fc…

MALICIOUS

PDF

85.7 KB Created: 2021-09-13 02:07:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 522f0c562a7d5b550ef3ac801909314d SHA-1: 043640deca96456a4f3d82e64fb21ac21ee7340d SHA-256: 56ab73b25a6547fced18a6ad0cf75ef04a6b300f0aab40ac90c36a8b0d5089d7
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • 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.
  • 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://smidgel.ru/uplcv?utm_term=how+to+increase+the+volume+on+android PDF link annotation
    • https://sklepbonus.pl/userfiles/file/95488701979.pdfIn PDF document text
    • http://diennuocdanang.com/uploads/image/files/diloviwabef.pdfIn PDF document text
    • https://adikkeempat.com/contents/files/76944139982.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16136efa4e85e2---67923806272.pdfIn PDF document text
    • http://sswjeans.com/files/66055822612.pdfIn PDF document text
    • http://chromoink.com/updates/file/50786479816.pdfIn PDF document text
    • https://marathonblainville.com/userfiles/files/7015528656.pdfIn PDF document text
    • http://lesen-und-schenken.de/userfiles/files/14562939548.pdfIn PDF document text
    • http://instit.ac/ckfinder/userfiles/files/buvobokulab.pdfIn PDF document text
    • https://santchavarabed.in/ckfinder/userfiles/files/40287818662.pdfIn PDF document text
    • https://currenwatch.myhost360.cn/file/upload/files/09-02-01-26-01-28.pdfIn PDF document text
    • https://www.delaneyllc.com/ckfinder/userfiles/files/buxukumib.pdfIn PDF document text
    • https://santehsevast.ru/userfiles/files/52932960571.pdfIn PDF document text
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130c43ebae01---junikenelupuverelub.pdfIn PDF document text
    • http://khyljg.com/uploadfiles/files/34397762707.pdfIn PDF document text
    • https://braveathlete.net/geektic/files/30549226635.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fb8eda16c5---6959343317.pdfIn PDF document text
    • http://bbmeti.it/userfiles/files/regazoruvokurarumapexamul.pdfIn PDF document text
    • https://serrechevalier-skifun.com/imagesfile/82082745420.pdfIn PDF document text
    • https://pima-alarms.rs/slicice/file/29267995288.pdfIn PDF document text
    • https://vietnaminsight.biz/ckfinder/userfiles/files/pimuvesumodiwaxudisomik.pdfIn PDF document text
    • https://ceral.pl/ceral/pliki/file/29361686228.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613834c6051ff---9230120116.pdfIn PDF document text
    • http://nowator-zpu.pl/userfiles/file/xanekurizoxe.pdfIn PDF document text
    • 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_off0000e809.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE809 10876 bytes
SHA-256: c5c791c302fe2a4e1443e7c199215992ce6e5a59c82b7b9ab50dfafaeed73d7d
font_01_sfnt_off000100f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100F8 18824 bytes
SHA-256: f7a0e50afffd4d11ea8078461ac8ebbda5ee04d22a68aaab7a201a02a0e997d3
font_02_sfnt_off00013164.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13164 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1