Malicious PDF — malware analysis report

Static analysis result for SHA-256 1cbb53b6f44ad3ff…

MALICIOUS

PDF

73.4 KB Created: 2021-10-03 22:54:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6480c9add9ef93d56c7af523f401e4fc SHA-1: d4e9354193acb58e27d989709420299ec92cddf9 SHA-256: 1cbb53b6f44ad3ffb919a3f22f014e05daa2e7bd763d0b38b096af314d17c693
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as a phishing trojan and ML classifier indicated maliciousness. It contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the overall structure strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7190

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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://inwebjor.ru/uplcv?utm_term=use+propensity+in+a+sentence PDF link annotation
    • http://aurangabadptti.com/ckeditor/ckfinder/userfiles/files/tujuwiwowufixafizud.pdfIn PDF document text
    • https://bulgariapools.com/contents/files/91444202126.pdfIn PDF document text
    • http://labradory.pl/file/32045056401.pdfIn PDF document text
    • http://jcon-aps.dk/userfiles/file/didulad.pdfIn PDF document text
    • https://buildingexpertsdirectory.com/ckfinder/userfiles/files/64257437904.pdfIn PDF document text
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/cf7a6025df3126e125878c15ebdd1faa/86934246680.pdfIn PDF document text
    • http://viettelhaiphong.me/data/dulieu/files/10769236269.pdfIn PDF document text
    • https://mlbcsimleague.com/ckfinder/userfiles/files/simusikukebufavedulagino.pdfIn PDF document text
    • http://cafegreenwichvillage.com/uploads/files/21753221044.pdfIn PDF document text
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/1613a8116d9fac---mamenemurofulis.pdfIn PDF document text
    • https://thebillionbottom.com/business_school/uploads/file/fibewugukiv.pdfIn PDF document text
    • http://liily.jp/upload/file/20210919155914.pdfIn PDF document text
    • http://nj-rshb.com/v15/Upload/file/2021929844292881.pdfIn PDF document text
    • http://czerwoneiczarne.pl/files/file/82111958292.pdfIn PDF document text
    • https://taiwan-tiaya.com/upload/tiaya_official/files/wesulapobujumisu.pdfIn PDF document text
    • https://broadcasthub.com/ci/userfiles/files/31003068135.pdfIn PDF document text
    • http://technology-mp.it/userfiles/files/wexij.pdfIn PDF document text
    • http://presupuestos.pavysan-bigmat.es/ckfinder/userfiles/files/jerulodon.pdfIn PDF document text
    • http://esipro.fr/userfiles/file/tosepemojiv.pdfIn PDF document text
    • http://mascotdd.com/file_media/file_image/file/29136615582.pdfIn PDF document text
    • http://kammerchor-lindau.com/file/betelukubolaxed.pdfIn PDF document text
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/3fccca2e45b440789ea05c49f54f765b/duvedugonu.pdfIn PDF document text
    • http://baoveantam.org/upload/files/69947515453.pdfIn PDF document text
    • http://pascalparrot.com/uploads/assets/file/mopuvedufobopufatekadok.pdfIn PDF document text
    • https://nhatngudongkinh.com/upload/ckupload/files/62934056076.pdfIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b0cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0CC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c8de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8DE 16808 bytes
SHA-256: 829bd18a7cd0d0dab006b951dd0deb8b4b2688c15f1e40478e9c4a82863ec43b
font_02_sfnt_off0000f331.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF331 10444 bytes
SHA-256: e9ce80b81805a1243635cad86ebce30273f70af1c0264a6f706694005e813af7
font_03_sfnt_off00010b0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B0C 16448 bytes
SHA-256: 0e4cde3d5bdd5452960de995a4807c8da4ec665155a9812e2f8e54e6c49b7878