Malicious PDF — malware analysis report

Static analysis result for SHA-256 f21377c4646fc779…

MALICIOUS

PDF

110.2 KB Created: 2021-09-07 12:15:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b5981cef008cc28725eeec95a30b230f SHA-1: c3da6f5c92a0d4e92207c5558f863fae06071162 SHA-256: f21377c4646fc779ac72669b73d3158118930b7b149beeb3d87c5a180fbbe4fe
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier as malicious. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm intended to redirect users. The presence of external URI heuristics and the ML classification indicate a high likelihood of malicious intent, possibly for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 https://queure.ru/uplcv?utm_term=manual+standing+wheelchair+price PDF link annotation
    • http://liily.jp/upload/file/20210821071203.pdfIn PDF document text
    • http://shtaket46.ru/page_edit/_samples/userfiles/files/sebozuvulesatesasur.pdfIn PDF document text
    • https://locktactyuma.com/ckfinder/userfiles/files/litaligobeseneru.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/rt5b194e2cjs8langvmoqacl63/15412785383.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b9fde28ce13---34566197141.pdfIn PDF document text
    • http://baove247.org/upload/files/batizobuzigi.pdfIn PDF document text
    • http://lnyuanzong.com/uploads/files/20210810174832.pdfIn PDF document text
    • http://clinical-pain.com/pds/userfiles/files/romuxusizazosukigi.pdfIn PDF document text
    • http://stl-hk.net/userfiles/sogeredapewi.pdfIn PDF document text
    • https://songhong-thudo.com/img/files/84618741046.pdfIn PDF document text
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0ecec231be---zajijelofepezejepozu.pdfIn PDF document text
    • http://itcck.org/upload/editor/file/mokebekadirixin.pdfIn PDF document text
    • http://wang023spa.com/userfiles/202108file/2021080402081970554.pdfIn PDF document text
    • https://thebillionbottom.com/business_school/uploads/file/65174166055.pdfIn PDF document text
    • http://franzoesischebulldoggen.eu/userfiles/file/dumeradaleworupa.pdfIn PDF document text
    • http://gulfcoolcontracting.com/uploads/userfiles/file/file/galexeragebuvusa.pdfIn PDF document text
    • http://coatsofarms.com.au/ckfinder/userfiles/files/manoras.pdfIn PDF document text
    • http://nfc.soo.jp/file/80750580312.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/1609e2324616df---43659106658.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/e56596b81dbcec7efe230bcbbb14a422/54409921618.pdfIn PDF document text
    • http://buergerforum-tirol.at/file/47691798930.pdfIn PDF document text
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/3fee11cea2f38a5983a088fd098fb6c4/41032019246.pdfIn PDF document text
    • http://tce.vn/imagesflashupload/file/48108025603.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_off000147c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x147C9 10852 bytes
SHA-256: cc8c95ac98ca6bd1097f4b1c2e713d68e5b46bb2374635f8155ee13ba8dec4eb
font_01_sfnt_off0001609f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1609F 19524 bytes
SHA-256: 613db3eb66b8634494d2c31ccb73d0bef79d793a3d8a12a0f633ce90e1cb6bc0
font_02_sfnt_off000192f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x192F7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.