Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a3a9bc17695730d…

MALICIOUS

PDF

89.5 KB Created: 2021-09-17 11:58:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 283b74f747a76836bf95913d7a0f704e SHA-1: c7c93467b54cca3d74e2738b40d4d8f79a0c9cec SHA-256: 1a3a9bc17695730d898b4bd55bfa30b48548f74e118e41c9a3d0b5063dc22d84
186 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics point to a lure for remote support tools, a common tactic for gaining unauthorized access. The presence of numerous external URLs, many hosted on potentially disposable domains, further supports a phishing or credential harvesting attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Remote-support tool lure high SE_REMOTE_SUPPORT_LURE
    Document instructs the user to install, open, or connect with a remote-support tool such as AnyDesk, TeamViewer, Quick Assist, or ScreenConnect — high-risk in an unsolicited document
  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://bestofbeer.ru/ckfinder/userfiles/files/51625305667.pdf In PDF document text
    • https://crossfitbeeshark.ro/app/webroot/files/userfiles/files/pezusafus.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138d05f4d1cf---70479797325.pdfIn PDF document text
    • https://familienbilstrup.dk/ckfinder/userfiles/files/70745232660.pdfIn PDF document text
    • https://icrs-as.com/userfiles/file/30835823813.pdfIn PDF document text
    • http://www.depomatrial.com/file/lomutawoguzuse.pdfIn PDF document text
    • http://laibros.com/ckeditor/userfiles/files/zuvubipiluxij.pdfIn PDF document text
    • http://piqiso.ru/userfiles/file/41513429081.pdfIn PDF document text
    • http://parentini.it/userfiles/files/kulawabif.pdfIn PDF document text
    • http://uktohabbarijamalta.com/files/file/52622757148.pdfIn PDF document text
    • https://piataafacerilor.ro/app/webroot/files/userfiles/files/mevizizuwivokomawoka.pdfIn PDF document text
    • http://home-plast.ru/foto/files/dinedego.pdfIn PDF document text
    • http://rigdrilling.org/userfiles/file/91263535041.pdfIn PDF document text
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/1f69gl78hmodtmnf3ptb0bilsh/96578177770.pdfIn PDF document text
    • http://ansonseatery.com/uploads/files/lewoboberagoputigabenum.pdfIn PDF document text
    • https://alaqart.atelierleuthold.ch/userfiles/files/fixila.pdfIn PDF document text
    • https://nguoixunghekiev.vn/userfiles/file/vumafubokavorub.pdfIn PDF document text
    • http://www.onlinenieuwsbriefversturen.nl/gebruikers/afbeeldingen/tepikilezawuvuvifitifiko.pdfIn PDF document text
    • http://napiarsaigh.com/images/suwizab.pdfIn PDF document text
    • http://kjphotocon.org/data/userfiles/files/pawixijozipovasasotafu.pdfIn PDF document text
    • http://dydlhx.com/upfiles/file///72088725029.pdfIn PDF document text
    • http://phongthuydotho.vn/upload/files/38314780880.pdfIn PDF document text
    • https://phnews.ro/files/file/12516345614.pdfIn PDF document text
    • https://tvsporedi.si/vsebina/naruzugudaj.pdfIn PDF document text
    • https://newsale.linyn.mobi/upload/ckeditor/pages/files/wovej.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=open+phone+on+pcPDF 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_off0000fa06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA06 9828 bytes
SHA-256: 95fffb3dfccd8768fc62f56fe1b24054d1e2b107126f02c11367081242081fb7
font_01_sfnt_off00010f85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F85 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012797.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12797 18920 bytes
SHA-256: 2701b27c694e5c82a3952ec03be83a9f2761176c8453213d3729303235e6f9e7