Malicious PDF — malware analysis report

Static analysis result for SHA-256 99013e05ac975a66…

MALICIOUS

PDF

129.3 KB Created: 2021-08-26 01:02:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 42c2faa59b9ad2cdb34a07f1360c93b5 SHA-1: 1bbac0ed669aa24446db968a8adde72c93ab99d4 SHA-256: 99013e05ac975a66d74075211ac45248817f53cbb8fb9f5fb16da01db1c9bf06
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the PDF structure itself is used to facilitate the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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://benthanhsgfarm.net/images/uploads/files/selutu.pdf In PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071719391c5a---21915159789.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/970c3258206e49fc63bcb2b14515cd0b/47804910619.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/161162462ef88a---2191849810.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/3bd3d62e95eb11426e287413da58b4f8/lituzowomovojinuziru.pdfIn PDF document text
    • http://sunnysidehigh65.com/clients/d/d0/d00d1ad1640c45b888f5e58ac216a5d1/File/suzetomujonorubenaruxobi.pdfIn PDF document text
    • https://broadcasthub.com/ci/userfiles/files/92907307212.pdfIn PDF document text
    • https://www.lindopoint.it/wp-content/plugins/super-forms/uploads/php/files/da22c64ae2a71af7cbc34b073ddbb3e5/lonepozemidexatareru.pdfIn PDF document text
    • https://spaslask.pl/wp-content/plugins/super-forms/uploads/php/files/5momua95lqmiq1sqvi586at65b/76090858332.pdfIn PDF document text
    • https://www.koreayokogawa.com/ckfinder/userfiles/files/donufigewe.pdfIn PDF document text
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/e9s0cse9ina6e1a734grcleguc/42180085686.pdfIn PDF document text
    • https://alexandrapanayotou.com/web/images/static/file/83712339458.pdfIn PDF document text
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/6640b63013230e3a590abfe4bf89ead6/34968998083.pdfIn PDF document text
    • https://avela.md/userfiles/file/wexexuwotizul.pdfIn PDF document text
    • https://tidymoney.com/ckfinder/userfiles/files/dojexofuwexagalabas.pdfIn PDF document text
    • https://legend-chang.com/UserFiles/files/mopopileroze.pdfIn PDF document text
    • https://myhoorayhealth.com/wp-content/plugins/super-forms/uploads/php/files/ngs4tuso043t6q094nacf7bsp2/pewijize.pdfIn PDF document text
    • https://cedarcreeksauce.com/wp-content/plugins/super-forms/uploads/php/files/48fffb470ed125ec4de854a30ea0479a/lojawixi.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/94a97e52f7cc26f729f9fbb6f5179c57/fikisotilominerewemopaxij.pdfIn PDF document text
    • https://asiastudy.in/ckfinder/userfiles/files/59763189539.pdfIn PDF document text
    • http://nutranghongngoc.com/media/ftp/file/fufefanij.pdfIn PDF document text
    • http://alexandercdg.com/clients/36029/File/53898395261.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f2ef4061b9d---83480048993.pdfIn PDF document text
    • http://yuhenganquan.com/userfiles/file/20210531194922_500549631.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=kingdom+of+flesh+and+fire+read+onlinePDF 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_off0001958d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1958D 18704 bytes
SHA-256: d435683900f4bed02fd72685361d08a72c1bb9c7a8e7d997ff0fc6608827b82d
font_01_sfnt_off0001c6c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1C6C5 10696 bytes
SHA-256: aecc8219d91a8babbe2dd7a8ecd4e626a175b541b20ff425deaa44e670568329
font_02_sfnt_off0001ded0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1DED0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1