Malicious PDF — malware analysis report

Static analysis result for SHA-256 31b5b0c8ef6cafef…

MALICIOUS

PDF

74.3 KB Created: 2021-09-24 16:21:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 96afcf63184a0041c72e2afbf373d7ac SHA-1: 5e49ea2903a758c9c513257d3fa11f9b9da9807a SHA-256: 31b5b0c8ef6cafef2dbc408c0051610c0af2a1c96581fadda5655722753d4d96
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous links pointing to compromised WordPress uploads and other disposable hosting, suggesting a link farm designed to redirect users. The PDF's structure and embedded URLs indicate it is likely used in phishing campaigns or to distribute further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://ketchas.ru/uplcv?utm_term=control+screen+orientation+apk+for+android+tv PDF link annotation
    • http://akcihlar.cz/userfiles/file/14515644213.pdfIn PDF document text
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141d937b3830---91776022075.pdfIn PDF document text
    • http://janaturismointegrato.com/uploads/file/56947051212.pdfIn PDF document text
    • https://moma-restaurant.com/wp-content/plugins/formcraft/file-upload/server/content/files/161366d48db006---vakulugonizasitaki.pdfIn PDF document text
    • http://ccsilver.kr/files/fckeditor/file/20826848726139796a11556.pdfIn PDF document text
    • http://yuhuimachinery.com/d/files/54403091898.pdfIn PDF document text
    • http://daiduongmetal.com/uploads/ckfinder/files/puvokokiditosozidez.pdfIn PDF document text
    • https://segurodegranizo.ar/noticias/fckeditor/file/60528643300.pdfIn PDF document text
    • https://slide-bearing.com/d/files/tatemekudozutodinelimed.pdfIn PDF document text
    • http://baruraprotidin.com/assets/ckfinder/core/connector/php/uploads/files/5254260138.pdfIn PDF document text
    • http://saluteebenesseresas.it/userfiles/files/85308658216.pdfIn PDF document text
    • http://sbstroy53.ru/img/files/24486438780.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/51433901198.pdfIn PDF document text
    • http://studiodrago.eu/userfiles/files/32953921426.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/c4b59ee7c83aa4bca3c3ac3d2aff8232/lawimetoxunot.pdfIn PDF document text
    • https://lacaune.hu/userfiles/file/vagujuzuwi.pdfIn PDF document text
    • https://cristalparkhotel.com.ve/ckfinder/userfiles/files/xobetebatolize.pdfIn PDF document text
    • http://topstec.com/d/files/xunegujisakevukuwuf.pdfIn PDF document text
    • http://aftckwt.com/uploads/file/turuburebit.pdfIn PDF document text
    • http://bjbtrh.com/files/pic/file/xotavirowotov.pdfIn PDF document text
    • http://101balkon.ru/upload/files/26666075125.pdfIn PDF document text
    • http://doctour.hu/uploads/ckfinder/userfiles/files/35113300461.pdfIn PDF document text
    • http://oryginalnedekoracje.pl/userfiles/file/texajelisela.pdfIn PDF document text
    • https://kitapkaplama.com/upload/ckfinder/files/nubilanajabaxinoravi.pdfIn PDF document text
    • http://www.prunay-en-yvelines.fr/ckfinder/userfiles/files/42183331648.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_off0000b69d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB69D 19252 bytes
SHA-256: 0dd4f21244dbc2e5acc3e1b2857ae38668df43260e6533fa50d8d0c6306d14e8
font_01_sfnt_off0000e821.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE821 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010038.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10038 10804 bytes
SHA-256: 5f34a3b9bc48b7b487c2772aac08a58aa5d107e248331892dd9d7e51782d7ad9