Malicious PDF — malware analysis report

Static analysis result for SHA-256 621401cfb4ddbdf4…

MALICIOUS

PDF

84.5 KB Created: 2021-09-14 13:24:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: f7f93b931bb46d051c23e6c17fff4eba SHA-1: 810a4628f61cf35d0b76f32d40a99ae4e2aa39e2 SHA-256: 621401cfb4ddbdf4b732f28c64a7323fcfdb681cf3b6c34d2d11558061d271ba
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection for 'Pdf.Phishing.Trojan'. The file contains numerous links, many pointing to compromised WordPress upload directories, suggesting it functions as a link farm to distribute malicious content or phish for credentials. The presence of external URIs and link farm indicators strongly supports a phishing or malware distribution attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://coretry.ru/uplcv?utm_term=8bp+apk+download PDF link annotation
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/1613de4e59f94a---memepon.pdfIn PDF document text
    • http://www.grifin.sk/files/zaruxiwabedejokiluv.pdfIn PDF document text
    • http://aurastaffing.es/upload/file/tevekaj.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/16130966804bff---zabawip.pdfIn PDF document text
    • http://boschvietnam.vn/files/usersfiles/files/norimazefubotugimezif.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1613897970ea72---joxogiranudirozisix.pdfIn PDF document text
    • http://bresky.cz/res/file/4444793540.pdfIn PDF document text
    • https://artcorner-fiberglass.com/userfiles/files/mupafujesepuwigu.pdfIn PDF document text
    • http://xlpe.net/Images_upload/files/zubupogamawipikefuja.pdfIn PDF document text
    • http://doctour.hu/uploads/ckfinder/userfiles/files/zelebirusopeluwefasijan.pdfIn PDF document text
    • http://gps-tw.com/CKEdit/upload/files/mabadufasinoxesofe.pdfIn PDF document text
    • http://faceconnects.com/ci/userfiles/files/wukewofudiwolekajesokubi.pdfIn PDF document text
    • http://globomax.eu/userfiles/file/wemelewomarinatiwe.pdfIn PDF document text
    • https://escaletravel.com/userfiles/files/gomobonune.pdfIn PDF document text
    • http://coquicart.com/ckeditor/ckfinder/core/connector/php/uploads/files/40976882117.pdfIn PDF document text
    • http://megatex-plast.ru/pub/file/xowobofu.pdfIn PDF document text
    • https://zmiz.hr/userfiles/file/xasajabuvusag.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161333d3bb4d1a---49155491284.pdfIn PDF document text
    • http://maketmaster.ru/admin/ckfinder/userfiles/files/nujofudizo.pdfIn PDF document text
    • http://fkhd.cz/data/img/xedojarefirijugo.pdfIn PDF document text
    • http://rockbond-aac.com/id-admin/fckImages/file/movoronirijixapatibamif.pdfIn PDF document text
    • http://bannails.com/fckeditor_userfiles/file/pifofilive.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_off0000e488.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE488 10224 bytes
SHA-256: 1a7c14b01f6bb96aa55f2b1f354061163daadb4430b62621783333d74abdbc24
font_01_sfnt_off0000fb57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB57 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011369.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11369 19196 bytes
SHA-256: 8c691762bf45bcb41e1134165d00e38f180195cd64e58414463459e9b65f90da