Malicious PDF — malware analysis report

Static analysis result for SHA-256 d3cc44b2e1be8560…

MALICIOUS

PDF

94.7 KB Created: 2021-09-23 13:00:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 466c5052b935cb247a2a6eda93bb4dc3 SHA-1: bcb989fece4382a29dd119256b7a104a04064a07 SHA-256: d3cc44b2e1be856004f26bb2dbdca5fb8c09e2837ded4da15cb03350dccde0d0
96 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous other PDF files hosted on various domains, some of which are identified as compromised CMS upload storage. The ML classifier strongly indicated maliciousness, and the structure suggests an attempt to lure users to download further malicious content or engage in phishing. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9888

Heuristics 5

  • 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://rosebankprimary.co.za/inc/ckfinder/userfiles/files/busojawo.pdf In PDF document text
    • http://imhang.com/fckeditor/userfiles/image/tubakekerotefadetexeja.pdfIn PDF document text
    • http://dbcasagayathottam.org/assets/uploads/cms_images/files/pivilozukumogi.pdfIn PDF document text
    • https://emilline.dk/ckfinder/userfiles/files/84471453478.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613baa2e373d5---88582896308.pdfIn PDF document text
    • http://shyjjc.com/v15/Upload/file/202191958312324.pdfIn PDF document text
    • http://euroear.eu/ckfinder/userfiles/files/82803187352.pdfIn PDF document text
    • http://solentpodiatry.com/jackvl940/web/content/images_uploaded/file/tuwogusogeje.pdfIn PDF document text
    • http://dtmaso.com/public_html/Imagens/file/48230422917.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161409c075b67e---6941703233.pdfIn PDF document text
    • http://air-con.ru/upload/files/6195453090.pdfIn PDF document text
    • https://www.hsbofmn.com/ckfinder/userfiles/files/42200499965.pdfIn PDF document text
    • https://kotata-zlin.cz/obr/clanky/file/26536997898.pdfIn PDF document text
    • http://gwtcs.org/Content/uploads/files/89657625152.pdfIn PDF document text
    • http://neteyes.eu/editor_up/31745270628.pdfIn PDF document text
    • http://vagtteam.dk/userfiles/Files/55776081222.pdfIn PDF document text
    • https://espritgt.com/userfiles/file/6520392930.pdfIn PDF document text
    • http://lamarchesainterita.be/lamarchesainterita/imgdb/news/files/bokamupuxivebi.pdfIn PDF document text
    • http://lunaleo.pl/userfiles/file/30954019711.pdfIn PDF document text
    • http://forti.in/userfiles/file/binoguxuvinufama.pdfIn PDF document text
    • https://cissud.it/uploads/ck_editor/files/21698132053.pdfIn PDF document text
    • https://dunakanyarfesto.hu/ckfinder/userfiles/files/wafefedaworevoxi.pdfIn PDF document text
    • https://aurorabersinar2.com/contents/files/luniwodiranewesufapom.pdfIn PDF document text
    • http://csc0871.com/userfiles/file/20210921122027_i817lw.pdfIn PDF document text
    • http://rhoptik.cz/klienti/devel/sneznerolby.cz/ckfinder/userfiles/files/regilawazumaguwu.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/161442ba57ffb0---larizijipepitenigebatag.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=awesome+words+that+start+with+pPDF 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_off00010d7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D7E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012595.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12595 10572 bytes
SHA-256: 44331b98ba8f531c6aac5e4890e10d938dfb16831b639d40022cb767b54be4e8
font_02_sfnt_off00013dcb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13DCB 17928 bytes
SHA-256: b81718c97442fc995d2794793e9900b9a3009037d846427be9813883db579dca