Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e630e243781a622…

MALICIOUS

PDF

77.6 KB Created: 2021-09-23 11:11:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 158e7d5197a4f5142e3b6b9a6a42971a SHA-1: bc633b29ea05ac7d4e29c3e577a7098ade5d36f0 SHA-256: 4e630e243781a6227ab1be1502df832b47e3de1ab7b1533aa141dd93f56e6a45
104 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to other PDF files, many hosted on domains flagged as link farms or potentially compromised CMS uploads. The ML classifier strongly indicated maliciousness, and the presence of multiple external links suggests an attempt to lure users to malicious content, likely for phishing or malware delivery. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 6

  • 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://chcial.ru/uplcv?utm_term=how+to+transfer+files+using+wifi+direct+in+android PDF link annotation
    • http://hnfhdc.com/UpLoadFile/2021090612451822367.pdfIn PDF document text
    • http://holland-ex.com/images/blog/file/wanuxa.pdfIn PDF document text
    • http://turningpointdigital.com/cote_dor_import/admin/ckfinder/userfiles/files/gajema.pdfIn PDF document text
    • https://parvazyab.com/basefile/api203/files/zetulomakixosuvibevi.pdfIn PDF document text
    • http://blevy.com/ckfinder/userfiles/files/43510128542.pdfIn PDF document text
    • http://elateridae.com/images/FCKeditor/file/66073846476.pdfIn PDF document text
    • http://ebara.com.hk/ckfinder/Zenith/userfiles/files/wifomizowunapatela.pdfIn PDF document text
    • http://full814.com/upload/files/sadiniz.pdfIn PDF document text
    • http://kemnhapkhau.com/upload/files/gefatudalopul.pdfIn PDF document text
    • http://ip-golubev.ru/ckfinder/userfiles/files/42639815205.pdfIn PDF document text
    • http://orderbestwings.com/uploads/files/66883455972.pdfIn PDF document text
    • http://darangyi.com/userData/board/file/65213355858.pdfIn PDF document text
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b862b4d8fb---tenokemizapimesi.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/70822065926.pdfIn PDF document text
    • https://ietc-oman.com/userfiles/files/fuwopomeketogesasov.pdfIn PDF document text
    • https://interativacorretora.com/fotosempresa/files/gekotireni.pdfIn PDF document text
    • http://mercuresamuichaweng.com/admin/file/40349370292.pdfIn PDF document text
    • http://thienminhgroup.com/uploads/userfiles/file/13565489097.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614b9fae267fe---89338650681.pdfIn PDF document text
    • http://etabetasurvey.com/userfiles/files/54705257352.pdfIn PDF document text
    • http://churchtextile.com/userfiles/file/fizuragogunoditefidesub.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/161336efe3c5d9---podapovukuru.pdfIn PDF document text
    • http://technimexvn.com/images/ckeditor/files/17533995646.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_off0000ca06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA06 17672 bytes
SHA-256: 68af0cbda2e2405b9c114ea51f57c4e145c5da5abcd23f2e6f4c187196861c8c
font_01_sfnt_off0000f7b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7B9 10828 bytes
SHA-256: 2e5b70b8e19b9dfe809649129c11aabe7859d123aa733e074319ea675f4d3bc4
font_02_sfnt_off000110a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110A9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1