Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa5877bac809581a…

MALICIOUS

PDF

69.9 KB Created: 2021-09-17 22:51:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 28af2094aba2e04bccda7e1c35df8744 SHA-1: 4ae129c277ec97c1405fe09d1e6aa67aef251093 SHA-256: aa5877bac809581a0f62a2e9050b54b7567a527cb41fa426af239c32ba84c4ee
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 http://maydemtienvn.com/upload/files/zoxoposokewiv.pdf In PDF document text
    • https://shaplaconsulting.com/app/webroot/ckfinder/userfiles/files/bibixedewupadejofabido.pdfIn PDF document text
    • http://fields-on-earth.com/images/blog/file/60892133170.pdfIn PDF document text
    • https://dalycity.com/wysiwygfiles/file/61402217225.pdfIn PDF document text
    • http://theurbanbazzaar.com/userfiles/file/93893842477.pdfIn PDF document text
    • https://it-remarketing.pl/app/webroot/media/files/20545383027.pdfIn PDF document text
    • http://projecthouse.bg/uploads/CKfinder/files/8934299779.pdfIn PDF document text
    • http://travel-door.com/userfiles/file/36924287966.pdfIn PDF document text
    • https://michelbarbot.com/upload/files/jiramubumoziluru.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134bd9f2c671---redesamelomoriz.pdfIn PDF document text
    • http://vnos.vn/app/webroot/uploads/files/485534090.pdfIn PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/6f98dc48fa517fb747d9a371eee96af8/puforib.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141ebcb60225---pozakazejusutufodaseja.pdfIn PDF document text
    • https://dom-titan.rs/files/gibafajifixubi.pdfIn PDF document text
    • http://fibertechnique.com/tmp/file/diwomigewakenine.pdfIn PDF document text
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/4a0258c90ee689a5cd20b434f7abc83a/43517770980.pdfIn PDF document text
    • https://sukienmiennam.com/userupload/files/lepajefizazumikawuto.pdfIn PDF document text
    • http://www.mab-solutions.fr/upload/file/74583958608.pdfIn PDF document text
    • https://socialacademy.gr/wp-content/plugins/super-forms/uploads/php/files/15797e95aa12be7434a15197a8fc2ef8/gejuzexilileluvag.pdfIn PDF document text
    • http://longarmacademy.net/fckeditor/userfiles/file/sorutusova.pdfIn PDF document text
    • http://kahounova.cz/userfiles/file/wibekesologafufonagizifom.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613f926688d90---munimejudalezof.pdfIn PDF document text
    • http://www.lifestaralberta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a7e20a3ee4---92640295128.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=the+catcher+in+the+rye+read+onlinePDF 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_off0000b4b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB4B4 14980 bytes
SHA-256: 7136022d4e810b60c87529615481627fe43be710cc98cfb648fc1f4a37afbaa3
font_01_sfnt_off0000da75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA75 10376 bytes
SHA-256: 86fbe6a0a004f988b40ea338569de03f7fa39a33d5666326006ecd2a0783e5e2
font_02_sfnt_off0000f1e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1E3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1