Malicious PDF — malware analysis report

Static analysis result for SHA-256 23c72ada2d5be0f1…

MALICIOUS

PDF

78.7 KB Created: 2021-09-05 07:22:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 1c851bc7482226118c7cf74d345761cc SHA-1: dc8cb0023889a29fe8d127628a79f47e7fbe3570 SHA-256: 23c72ada2d5be0f163265fa32459d4d0ed74ba6c01e32b6d76d291c4f701f284
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://allytemp.ru/uplcv?utm_term=engineering+drawing+objective+type+question+bank+pdf PDF link annotation
    • https://gbeequestriansurfaces.com/wp-content/plugins/super-forms/uploads/php/files/vj7a7blhiq38lv1sar431r2qbv/dunimapubowimubiji.pdfIn PDF document text
    • https://egca.fr/userfiles/file/67685288335.pdfIn PDF document text
    • http://sculecuacumulator.ro/app/webroot/files/userfiles/files/jezomerideletab.pdfIn PDF document text
    • http://opusbiz.kr/data/editor/file/116662288260e94ddfecdb5.pdfIn PDF document text
    • http://wchs65.org/clients/b/bb/bb65574a37642f7fe3135935df861e67/File/jatodonufokuxuleripote.pdfIn PDF document text
    • https://portugaliaimagyarok.com/ckfinder/userfiles/files/neziwujutadon.pdfIn PDF document text
    • http://blackshirts1962.com/clients/f/f2/f245580d3072b78cda2271cf7a7e3f61/File/947915872.pdfIn PDF document text
    • https://alsterparkett.de/wp-content/plugins/super-forms/uploads/php/files/2d6mbg5o3jhvo4of4iu8pvim9c/95413012336.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/c14d93ae70f472d686e7f2de8f13b1db/xejikubogifufaf.pdfIn PDF document text
    • http://homestationrealty.com/userfiles/files/savafitodejuku.pdfIn PDF document text
    • https://art-eria.pl/mandarynka/pliki/files/domivafonojalogiv.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/160be93b7753b0---zoverutijotabor.pdfIn PDF document text
    • http://evo-models.com/uploads/userfiles/files/90416259471.pdfIn PDF document text
    • http://elanaclub.ru/userfiles/file/ligigugedadoximuziwog.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/16099d7adada9e---pototu.pdfIn PDF document text
    • http://olsztyntransportmedyczny.pl/userfiles/file/kererudiratosoruw.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/16boi1jqssec5lhk1tuort32mk/wokevesepemokapifane.pdfIn PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/160c0240d83734---68457599308.pdfIn PDF document text
    • https://afayl.com/userfiles/file/41342219241.pdfIn PDF document text
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608557b47cfb1---68388216858.pdfIn PDF document text
    • http://bangtaisay.com/uploads/userfiles/file/8702214102.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f8fed847127---44726182515.pdfIn PDF document text
    • http://massimobertoarchitetto.com/userfiles/files/3389374213.pdfIn PDF document text
    • http://crabandclaw.com/uploads/files/86491872269.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_off0000ce90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE90 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e6a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6A2 16752 bytes
SHA-256: 7325c2eaa64c99422f5b35a9907004aff3d3339dcef8772e0c6428f883c126e4
font_02_sfnt_off000111b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111B3 11608 bytes
SHA-256: a2e5691259df4286dbb3c0bc5580dbee6606a204c977bc0a5ba392e65efcdccf