Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ad551ff06e34a72…

MALICIOUS

PDF

118.8 KB Created: 2021-04-27 14:49:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: c6e3ec2c1f7cbf30491a88c900f7d92b SHA-1: f342c51e3dfd6ec09a79f84b812ec982f93280cb SHA-256: 4ad551ff06e34a72efdc0f7c7ab8020dffa1fda21ff7bd817450b64859d767ba
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or distributing malware. Although no scripts were extracted, the structure and URL patterns suggest an attempt to manipulate search engine results or direct users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://seiary.com/sites/default/files/webform/rec/jizexatunurometubukos.pdf In PDF document text
    • http://russian-ice-spb.ru/sites/default/files/webform/files/fapulewamekunasu.pdfIn PDF document text
    • https://architecturaldesigninc.com/sites/default/files/bujepalifomi.pdfIn PDF document text
    • https://architecturaldesigninc.com/sites/default/files/56675633315.pdfIn PDF document text
    • http://www.grotekeukens.be/sites/default/files/webform/gmawards2018/48103714077.pdfIn PDF document text
    • http://www.muttypawsacademy.com/sites/default/files/webform/vaccines/30199048500.pdfIn PDF document text
    • http://spotlight-sites.com/sites/default/files/webform/jalipoxelelikepobolid.pdfIn PDF document text
    • http://seiary.com/sites/default/files/webform/rec/47545977947.pdfIn PDF document text
    • https://www.jwico.com/sites/default/files/webform/23528315583.pdfIn PDF document text
    • http://www.grotekeukens.be/sites/default/files/webform/gmawards2018/jebumimebugamoto.pdfIn PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/41266633523.pdfIn PDF document text
    • http://fedorahosted.org/lohitIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=john+rawls+theory+of+justice+pdf+in+hindiPDF link annotation
    • https://lib.asu.edu/system/files/webform/dilitopuwivane.pdfIn PDF document text
    • https://thesanfordschool.asu.edu/sites/default/files/webform/lezedatabamivija.pdfIn PDF document text
    • https://community.princeton.edu/system/files/webform/tujuxegagisezemesolut.pdfIn PDF document text
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/tivajojisepizoni.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://scripts.sil.org/OFLIn PDF document text
    • http://www.geocities.com/mitra_anirban/hobbies.htmGNUIn PDF document text
    • http://www.gnu.org/copyleft/gpl.htmRegularIn PDF document text
    • https://savannah.gnu.org/projects/freefont/In PDF document text
    • http://www.gnu.org/licenses/In PDF document text
    • http://www.gnu.org/copyleft/gpl.htmlIn PDF document text

Extracted artifacts 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_006_off0001847c.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x1847C 19360 bytes
SHA-256: b02309f6eafa19c1fcc3d7e85136d0895ccd3ed22f69ca69d1ce7a2cd778dfee
font_00_sfnt_off00014430.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14430 5504 bytes
SHA-256: bdaca6633528f594e2022caa648d7f30049ecd639c992082e3f3ed5aad07fa9e
font_01_sfnt_off000156fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x156FD 3720 bytes
SHA-256: 6539b129c5cd894636dc8f40f53a156c00c8f46378ab4f137c96d687a1cff6ed
font_02_sfnt_off0001625f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1625F 9956 bytes
SHA-256: 0aaa88eb078d64c6b4456aedd4ba2b59b8f1da9dbabef7585d2fe676a717074b
font_04_sfnt_off0001badf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1BADF 6112 bytes
SHA-256: 7a1b8a016f4bdf992a8cd796afd9e376e8afb5e4bc7ee7c9dd1afd274536ccf5