Malicious PDF — malware analysis report

Static analysis result for SHA-256 43a48a488753ccee…

MALICIOUS

PDF

86.4 KB Created: 2021-09-17 21:30:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 197b44688d7a94e6bbc90001bda494bc SHA-1: 6da184f06c2715befcac950a6541d236453fe88a SHA-256: 43a48a488753ccee9b287b9c85cdcd56349aac6840068db391cf03cdb05a1c95
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs that form a link farm, with many pointing to disposable hosting or compromised CMS upload storage. This suggests the document is designed to lure users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://infrive.ru/uplcv?utm_term=monash+health+contact PDF link annotation
    • http://abwingsjanaf.com/uploads/files/22495735811.pdfIn PDF document text
    • https://cedria.es/DOCUMENTS/FotosFCKEditor/file/27303598305.pdfIn PDF document text
    • https://autonoleggioassereto.com/file/gorukulexodenexakokez.pdfIn PDF document text
    • https://tumsad.org/img/editor/image/file/54100905530.pdfIn PDF document text
    • https://minjar.mebel18.com/uploads/files/vejutonawunulawobudemem.pdfIn PDF document text
    • http://twsl.mingann.info/upload/ckfinder_temp/files/20210915094836.pdfIn PDF document text
    • http://alde-pace.org/ckfinder/userfiles/files/96829573544.pdfIn PDF document text
    • https://www.gryf-wet.pl/ckfinder/userfiles/files/25572443177.pdfIn PDF document text
    • http://edeins.com/userfiles/file/71404976592.pdfIn PDF document text
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/ced3fdaed89525630b4db376aeeed0ed/xaxugitewibebifi.pdfIn PDF document text
    • http://laserbeautymachine.net/d/files/sorugur.pdfIn PDF document text
    • http://curvesncontours.com/userfiles/file/xegurizatewozopexod.pdfIn PDF document text
    • https://www.mftelhas.com.br/adm/Editor/ckfinder/userfiles/files/gururupuveninonefopupi.pdfIn PDF document text
    • https://festivalecolo.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613a7b5b5785b---vebanapijavonuxufumo.pdfIn PDF document text
    • http://ateliergermain.net/sites/default/files/file/nubofokalur.pdfIn PDF document text
    • https://fobh.net/userfiles/files/nibiziluniwomomafezaw.pdfIn PDF document text
    • http://tochalco.com/uploads/files/17975227767.pdfIn PDF document text
    • http://bsa.by/ckfinder/userfiles/files/bopipariluv.pdfIn PDF document text
    • http://crocepadrekolbe.it/userfiles/files/volirizowifabunoroz.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613fe4ae09116---13568167335.pdfIn PDF document text
    • https://dgssu.com/upfolder/e/files/20210909060258.pdfIn PDF document text
    • http://vetcasatenovo.it/userfiles/files/bavuwanuf.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_off0000ee18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE18 10128 bytes
SHA-256: 1f544082d9356a26f7c126b4ce93ba4a955a36c6e5d5e78f72fcac372e4709e9
font_01_sfnt_off000104b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104B4 18476 bytes
SHA-256: 9d7e83a2ea395e9820f18cea2aff9f75b07db01005016133b47672ed69ff9c25
font_02_sfnt_off00013479.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13479 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1