Malicious PDF — malware analysis report

Static analysis result for SHA-256 1af278ac561959dc…

MALICIOUS

PDF

80.1 KB Created: 2021-09-17 16:50:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 6633309950c7907e7c2bfb34bd91d376 SHA-1: 454a8c374e1452ee0662d4afd489fadf4e096dc8 SHA-256: 1af278ac561959dc86de5e4f62dff9a0a9e86c5a933b5f66b17eaf968fcc7b4f
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 an ML classifier flagged it with high confidence. It contains numerous external links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users. The presence of these links indicates an attempt to lure users to malicious sites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://dongciao.com/uploads/files/202109061834302123.pdf In PDF document text
    • http://xn----7sbjvweekof5d.xn--p1ai/files/files/47947123435.pdfIn PDF document text
    • https://orderpoet.com/ckfinder/userfiles/files/genezimuva.pdfIn PDF document text
    • http://rfinshaat.az/userfiles/file/15343852701.pdfIn PDF document text
    • http://gonvvama.net/filespath/files/20210917055510.pdfIn PDF document text
    • https://perfecthospitals.org/FCKeditor/file/kepureke.pdfIn PDF document text
    • https://mbzl-pro.xyz/web/img/podborky/files/60810761437.pdfIn PDF document text
    • http://fine-cottage.ru/userfiles/file/481354341.pdfIn PDF document text
    • https://kasihpaham.com/contents/files/lejugoliki.pdfIn PDF document text
    • http://ziva-muzika.cz/files/file/31310027186.pdfIn PDF document text
    • http://stin-verdon.fr/assets/Image/files/ziles.pdfIn PDF document text
    • http://www.bufolari.com/public/immagini/file/bofojadunite.pdfIn PDF document text
    • http://openendrep.com/userfiles/files/sapusixutukolawome.pdfIn PDF document text
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/77tvt3e43qd47d4mkdflsndlan/75142251885.pdfIn PDF document text
    • https://baoyi-chuck.com/ckfinder/userfiles/files/vowuvon.pdfIn PDF document text
    • https://morabia.fi/images/file/ritezesunopawugodufosex.pdfIn PDF document text
    • http://mikllc.mn/uploads/files/26146074399.pdfIn PDF document text
    • http://koreanhotpot.com/uploads/files/judegirofe.pdfIn PDF document text
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/3bc4slh6a4902lhqkovaef70se/89062129109.pdfIn PDF document text
    • http://volkshilfe-ktn.at/images/content/files/jefajutuvuwapodizirojaga.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143d05b88513---61970614477.pdfIn PDF document text
    • https://amthanhanhsangchinhhang.vn/upload/files/29790987368.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/161446c3a3c7e0---99445825646.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=usmle+step+2+ck+pdf+first+aidPDF 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_off0000d23d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD23D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ea4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA4F 18416 bytes
SHA-256: 1fa534d98d4f3a4f0fba776db486dd781692c7894b06e6ead45db8843e5ad950
font_02_sfnt_off00011a1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A1E 10776 bytes
SHA-256: 750b997319678e49984d43fe75d6786b265587246f40fce598730270e1755598