Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc6d3530a0e6726e…

MALICIOUS

PDF

73.2 KB Created: 2021-09-24 17:16:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 607d089b6aff371459e951d5ce4a9634 SHA-1: a3d2c3dc49dfd4f4b6b1c0b99b92523a312fb979 SHA-256: fc6d3530a0e6726ecc5128f7d53cd9e2a64c20121271ebc875a0462b67667297
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or are part of a link farm designed to obscure the final destination. Heuristics indicate these links are used to distribute content, with one URL specifically flagged as a potential phishing or trojan delivery mechanism. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9915

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://balalajka.nu/media/zademofoxunisapenijolevoj.pdf In PDF document text
    • http://ettorebelfioreliutaio.it/userfiles/files/95739868637.pdfIn PDF document text
    • http://artechq8.com/beta/uploads/files/22882739924.pdfIn PDF document text
    • http://sten.kr/club/data/userfiles/file/20210902040056.pdfIn PDF document text
    • https://hpx.com.ua/wp-content/plugins/super-forms/uploads/php/files/bed1eb3724605a1c3cc85c1ab9de251b/3640493802.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/957dcb569b75e0d0a931cbeac146b980/92693195676.pdfIn PDF document text
    • http://gtlitalia.com/userfiles/files/jeluzukomasowukop.pdfIn PDF document text
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/ca8891490e0d6bfe154449ee39479da0/99596745068.pdfIn PDF document text
    • https://nakatarikaszel.pl/app/webroot/userfiles/file/gijupinar.pdfIn PDF document text
    • https://abyway.lv/images/ck_images/files/71379607078.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1614161ec7b133---madimom.pdfIn PDF document text
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/dd8c9a8820aa605de98982b534e80a8c/9669954099.pdfIn PDF document text
    • http://cowmoo.org/ckfinder/userfiles/files/banasopewetudoxisab.pdfIn PDF document text
    • http://liyangah.com/Upload/file/vaxumadikivowigoni.pdfIn PDF document text
    • https://onecre.com/images/content/files/7861725603.pdfIn PDF document text
    • http://eptesteplelek.com/uploads/file/24496748570.pdfIn PDF document text
    • https://www.mftelhas.com.br/adm/Editor/ckfinder/userfiles/files/50936230296.pdfIn PDF document text
    • http://firmen-bekleidung.at/userfiles/file/21630963476.pdfIn PDF document text
    • https://geneolock.com/ckfinder/userfiles/files/14977526098.pdfIn PDF document text
    • https://ph2020.org/ckfinder/userfiles/files/8149642144.pdfIn PDF document text
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613fdbe6a358a---pelisu.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/1614bd852e2d0d---dupiturilidukebebalotu.pdfIn PDF document text
    • https://www.kadeavenue.com/wp-content/plugins/super-forms/uploads/php/files/1fe2fdd224d52bbac94cf6df9d80787c/sizajufopimepek.pdfIn PDF document text
    • https://jin-ji.com/upload/files/tilurineso.pdfIn PDF document text
    • http://giaexploring.it/userfiles/files/vewezivifadakelezabulaj.pdfIn PDF document text
    • http://unnatiwelfareorganization.com/ckfinder/userfiles/files/3379296673.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=free+fire+apk+linkPDF 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_off0000ba95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA95 18172 bytes
SHA-256: 32664e347628387b3534612ab733fdeda4428605c739b8fea09905c7d7efb3de
font_01_sfnt_off0000e8da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8DA 10036 bytes
SHA-256: 7767e382ce59fde54d0b7692de47a5a42672cc043b33b50d34e4f2f3f56ee1e6
font_02_sfnt_off0000ff24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF24 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1