Malicious PDF — malware analysis report

Static analysis result for SHA-256 541c552a05d42e9b…

MALICIOUS

PDF

81.9 KB Created: 2021-09-08 19:17:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: f804282da38e69d07f2c5a84c9228d2c SHA-1: 4bd1b6d8cbb46414cfdace81daea855d5272db6f SHA-256: 541c552a05d42e9bca8e5c67058079da51b6cc41075d5f4346198a415385f877
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to potentially compromised CMS upload directories. The presence of numerous unknown reputation URLs suggests a distribution mechanism for further malicious content or phishing attempts.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613124ae2d617---87214800481.pdf In PDF document text
    • http://attlas.center/userfiles/file/baluvejivikuvaxuguwoju.pdfIn PDF document text
    • https://flardochform.se/userfiles/file/94145879347.pdfIn PDF document text
    • http://sanfrancescovet.com/userfiles/files/dajakanubogezoxafew.pdfIn PDF document text
    • https://limberhurstgallery.com/imageuploads/file/zexureje.pdfIn PDF document text
    • https://detmers-kontejner.hr/files/rulamigekaxaf.pdfIn PDF document text
    • http://ser-buk.com/userfiles/file/5957625595.pdfIn PDF document text
    • http://f-okinawa.com/img/tmp/file/24162203360.pdfIn PDF document text
    • https://www.idd.no/ckfinder/userfiles/files/62474297632.pdfIn PDF document text
    • http://bagiez.com/userfiles/file/pesover.pdfIn PDF document text
    • http://sgpeo.pl/users/file/seziw.pdfIn PDF document text
    • http://the100voicesofgospel.ch/fichiers/newsletter/file/78770167754.pdfIn PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137e736500c4---kabekewedakitanuzo.pdfIn PDF document text
    • http://samurairamenbar.com/uploads/files/34987041771.pdfIn PDF document text
    • http://teleserviciomalaga.com/ckfinder/userfiles/files/26536574224.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/ec7cbbdcdfc7d7b0fa1d1fc7f52ddfdb/fazoxa.pdfIn PDF document text
    • http://3e3i.com/UserFiles/file///3711819180.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613660090d5b4---10607379958.pdfIn PDF document text
    • http://allasclub.com/campannas/file/14214794548.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/161374037c354e---66707124747.pdfIn PDF document text
    • https://propiedades.net/ckfinder/userfiles/files/84583363943.pdfIn PDF document text
    • http://sungder.com/upload/49909472073.pdfIn PDF document text
    • http://udmvdpo.ru/images/files/miwizexikeli.pdfIn PDF document text
    • https://smwebtechnology.com/arishayurveda.com/userfiles/file/semawekimujufelupivosa.pdfIn PDF document text
    • http://vrieshorst.nl/images/uploads/file/xovavojuvawawa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=albania+travel+guide+pdfPDF 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_off0000da2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA2A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f241.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF241 10672 bytes
SHA-256: de3c6c07dd0704b866282afee3ffec35d787da6d8e02432ce447f294f6aa4967
font_02_sfnt_off00010a6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A6C 18600 bytes
SHA-256: 36052a05b9ca4c122509030c8e65d9bf06433f15f7fc8691ca734c5bfd68d615