Malicious PDF — malware analysis report

Static analysis result for SHA-256 1d7f7f4535f8b214…

MALICIOUS

PDF

80.5 KB Created: 2021-09-23 09:37:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: abcc3affcff522a615311e460c37aa88 SHA-1: e81cfbf3ef68f9b65a336e9290aef91c5e1fc3fb SHA-256: 1d7f7f4535f8b21401c4cf64610d04c89e82a321741083d43b0fb377a8507317
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a phishing or trojan threat. Heuristics reveal it functions as a link farm, pointing to numerous disposable domains and compromised WordPress sites, likely to host malicious content or phishing pages. The embedded URLs and the nature of the heuristics strongly suggest an attempt to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://smidgel.ru/uplcv?utm_term=javascript+get+keyword PDF link annotation
    • http://librojuridico.com/aym_images/files/xebasugitifupadalunag.pdfIn PDF document text
    • http://ez-surveying.com/htdocs/cljr/data/files/76774091682.pdfIn PDF document text
    • https://edusfera.pl/upload/file/zonenexatan.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/1613b3e37bf908---fuxemukizixot.pdfIn PDF document text
    • http://loaamtran.vn/files/usersfiles/files/75313127860.pdfIn PDF document text
    • http://ibconsulting.it/userfiles/files/7749341931.pdfIn PDF document text
    • http://sushrutproctology.org/ckfinder/userfiles/files/63194616498.pdfIn PDF document text
    • http://kriosispl.com/cote_dor_import/admin/ckfinder/userfiles/files/fojomufoluvomafiripa.pdfIn PDF document text
    • http://grupopiscis.com/upload/files/jazan.pdfIn PDF document text
    • https://jurvamartin.com/userfiles/file/limodu.pdfIn PDF document text
    • https://fnb-concepts.com/images/uploads/files/mabowaso.pdfIn PDF document text
    • http://londonjip.com/userData/board/file/62018933599.pdfIn PDF document text
    • http://mirutte.com/newsfiles/files/vopoluporosuzexaw.pdfIn PDF document text
    • http://elfuklid.cz/foto/Image/file/90019898369.pdfIn PDF document text
    • https://seikai.jp/free_images/files/jufesuwovefunuxar.pdfIn PDF document text
    • http://getdol.com/page_data/file/70752024412.pdfIn PDF document text
    • https://grnca.org/img/files/files/13913397008.pdfIn PDF document text
    • http://tdsns.ru/userfiles/file/35828179598.pdfIn PDF document text
    • https://turismopontevedra.com/ckfinder/userfiles/files/nupiwipavedawilogewal.pdfIn PDF document text
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614bf8a7f4172---35564142790.pdfIn PDF document text
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614983f746f1c---63860905656.pdfIn PDF document text
    • http://www.koeru.eu/failid/file/wumirasoripupumomalefava.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_off0000d4f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4F4 10888 bytes
SHA-256: 2d21b9e18ed9ef30c6eb7898853e32e8b3bde6af58183c751ff3c3322499cf06
font_01_sfnt_off0000ee33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE33 18312 bytes
SHA-256: 75c481473419bfcbd194307b93bb5aa9b40438676d5de5378f2df96abe8f4678
font_02_sfnt_off00011d24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D24 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1