Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f7fcb1eac346100…

MALICIOUS

PDF

85.5 KB Created: 2021-09-15 17:42:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 5ad910ef8353dbafdf2897d998ce2367 SHA-1: 3d998cfcaefa14499548afa8b2b219d9a5db6b91 SHA-256: 9f7fcb1eac3461003399f97397026fd8ff02b9a47c8cc4dad4cd5270cb1b1e6e
86 Risk Score

Malware Insights

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

The sample was flagged as malicious by an ML classifier and contains numerous embedded URIs, many pointing to disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the PDF is a non-clustered link farm, suggesting its purpose is to redirect users to potentially malicious sites. One URI points directly to an IP address, increasing suspicion.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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 http://thsport.dk/userfiles/file/45098780897.pdf In PDF document text
    • https://royal-art.pl/uploads/userfiles/files/35311032223.pdfIn PDF document text
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/16130823a47753---13162624.pdfIn PDF document text
    • http://ekopaczka.pl/imgbrama/files/vivokelufax.pdfIn PDF document text
    • http://tuzvedo.hu/elemek/file/mawenujamebe.pdfIn PDF document text
    • http://huseyindurmuslar.com/images_upload/files/76519262404.pdfIn PDF document text
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613590e8045fa---kigisisuzurutavatu.pdfIn PDF document text
    • http://dvg.asia/ckfinder/uploadfiles/files/vodawitoledamekasibek.pdfIn PDF document text
    • https://jnvhardoi.org/ckfinder/userfiles/files/2901202830.pdfIn PDF document text
    • https://letajicikoberce.cz/userfiles/file/wexulakukitoronetake.pdfIn PDF document text
    • https://xn--72ca1bzcdf9cg5df4n5a8cei.com/userfiles/files/32078608009.pdfIn PDF document text
    • http://whuntex.info/userfiles/file/lodubuxovukowatapibudoj.pdfIn PDF document text
    • http://104.156.58.56/~web2inbox/wp-content/plugins/formcraft/file-upload/server/content/files/16135502471af3---70810517146.pdfPDF link annotation
    • http://canhtoanland.com/upload/files/nixeburekopox.pdfIn PDF document text
    • https://nutritie-metabolism-sanatate.ro/app/webroot/files/userfiles/files/zaluxa.pdfIn PDF document text
    • http://edumedcare.pl/upload/files/23343441553.pdfIn PDF document text
    • http://kxqcgs.net/filespath/files/20210912140759.pdfIn PDF document text
    • https://maharajganjtimes.com/assets/ckfinder/core/connector/php/uploads/files/xobuxevo.pdfIn PDF document text
    • https://atputasbazes.lv/images/userfiles/files/tozonexifuwopafasor.pdfIn PDF document text
    • http://qazaqbanki.kz/data/content/files/bukapawetovirok.pdfIn PDF document text
    • https://ivanamihic.com/files/82519609201.pdfIn PDF document text
    • https://swagath.co/new/ckfinder/userfiles/files/18948336244.pdfIn PDF document text
    • http://hangquangauto.com/files/robaletalisilejuwulubor.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=best+app+cloner+appsPDF link annotation
    • http://irodori.kir.jp/files/file/bafukupepirolejud.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_off0000e9f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9F5 18148 bytes
SHA-256: 62fffc5ea7b24b0077afae2f22422786d062e91cf94ec2e6255a9fba8438ee4f
font_01_sfnt_off00011965.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11965 10328 bytes
SHA-256: 4ad74ec9870722217475b3cc7df66b1d4fcf786c60ab2023f662ec48c1dc654c
font_02_sfnt_off000130ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130EA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1