Malicious PDF — malware analysis report

Static analysis result for SHA-256 c852fcfa458a63c1…

MALICIOUS

PDF

69.7 KB Created: 2021-10-01 09:19:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 97658c87f3de1d4b840d3df84efda83f SHA-1: f9d076a83638878d3b46dec8ce237cdbd3618b3d SHA-256: c852fcfa458a63c1541b224f9a04a8af03508fbe1818249ea5b92b9a522cf3b1
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to potentially compromised WordPress sites or disposable domains. The presence of numerous unknown URLs suggests a distribution mechanism for further malicious content or phishing attempts.

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://aqcorth.specialty-match.com/upload/files/gazuragadamedux.pdf In PDF document text
    • http://charontrade.hu/data/file/damagegus.pdfIn PDF document text
    • http://sskj.pl/userfiles/file/fesuzudelotoz.pdfIn PDF document text
    • https://festivalecolo.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16133ac263fc46---numivip.pdfIn PDF document text
    • http://2rent.gr/userfiles/file/bukodutomuwiwom.pdfIn PDF document text
    • https://aprilboya.com/userfiles/file/gewodukelategupifefenuw.pdfIn PDF document text
    • http://e-sheremet.com/img/manodulawigeziwiwutazo.pdfIn PDF document text
    • https://rieker-consulting.eu/files/file/70782320579.pdfIn PDF document text
    • http://evaemlak.com/userfiles/file///27783958925.pdfIn PDF document text
    • https://ukmriptek.org/codeIgniter-hmvc/userfiles/files/71717045218.pdfIn PDF document text
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/8b26861fc5d97daf2bb48c7f484e0dc0/jefofelopezonadasugasofu.pdfIn PDF document text
    • https://almudenafernandez.co/ckfinder/userfiles/Files/11301152870.pdfIn PDF document text
    • http://cortocircuito.trialpanel.com/images/Upload/files/29971838088.pdfIn PDF document text
    • http://hytechplus.com/userfiles/file/bifofuximapebuxij.pdfIn PDF document text
    • https://mk-sito.it/uploads/file/wupomijudenabokoguj.pdfIn PDF document text
    • https://j26clean.com/upload/files/52700707775.pdfIn PDF document text
    • https://diphong.com/uploads/rotomig.pdfIn PDF document text
    • http://vector-mebel.ru/uploads/files/tuwevelegujufifosoganarug.pdfIn PDF document text
    • https://mountainbrookbuilders.com/home/mountain/public_html/ckfinder/userfiles/files/43132182214.pdfIn PDF document text
    • http://ppfi-online.com/userfiles/file/buxolulimuwejajowupo.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/pn0e86tcfb8go08cg3ss8a46q8/kojib.pdfIn PDF document text
    • https://copab.tn/216mag.svn/uploads/files/9220937452.pdfIn PDF document text
    • http://immodraft.de/images/architekten_agentur_images_/file/devir.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=nexus+one+pricePDF 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_off0000b1a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1A8 15880 bytes
SHA-256: 53ebcd757413c46f3182ef70f7498e6a0035c445ce3e9c4ff2b7a561b1f4da8e
font_01_sfnt_off0000da1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA1A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f231.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF231 10240 bytes
SHA-256: bb3f244961ec718db64469e3cc31d1a07dc1820c9a98805f3310d682588df6af