Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef6577d29c28c213…

MALICIOUS

PDF

101.9 KB Created: 2021-05-20 13:18:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 919723e520c5efa37c6156a1376cf619 SHA-1: 595c1d4f328c4a762f601c89add69d7ffe4566a5 SHA-256: ef6577d29c28c21328d8ee35ba7d1c939f003ebdc35d56add5ab1cb690802a98
164 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. The presence of numerous external links, including one to `golowaki.ru`, suggests a phishing or malicious content distribution attempt. The heuristic `PDF_SEO_LINK_FARM` indicates a large number of external PDF links, likely to manipulate search engine results or host further malicious content. The `SE_DOWNLOAD_BUTTON` heuristic suggests a lure to trick users into downloading something.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://golowaki.ru/strik?utm_term=download+bts+wings+tour+final+in+seoul+day+3 PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4486192/normal_5fdf81608fe72.pdfIn PDF document text
    • https://gitonuzeku.weebly.com/uploads/1/3/4/7/134764432/5012457.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4477401/normal_5fe30ef44c5ee.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4371523/normal_601b35ce5bbef.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4472182/normal_603d4ca73f3ce.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476939/normal_6052709117036.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4478134/normal_6029dd64944fe.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4495269/normal_5ffe7f25307b1.pdfIn PDF document text
    • https://zifimegepero.weebly.com/uploads/1/3/4/6/134601706/7092795.pdfIn PDF document text
    • https://tusuwijajibu.weebly.com/uploads/1/3/4/5/134517525/8591622.pdfIn PDF document text
    • https://pisubemiduburor.weebly.com/uploads/1/3/1/3/131380627/18f08d4c545cd.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446152/normal_604a550eb0c68.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/boxujetanonikuv/essential_university_physics_volume_2_4th_edition.pdfIn PDF document text
    • https://s3.amazonaws.com/kudowo/school_calendar_2021_south_africa.pdfIn PDF document text
    • https://s3.amazonaws.com/garorowa/capitalism_the_unknown_ideal_ayn_rand.pdfIn PDF document text
    • https://s3.amazonaws.com/dinigugaxej/hens_night_invitations_free_templates.pdfIn PDF document text
    • https://s3.amazonaws.com/firudegix/difference_between_nikon_sb-700_and_sb-800.pdfIn PDF document text
    • https://s3.amazonaws.com/mivokozibu/16072292428.pdfIn PDF document text
    • https://s3.amazonaws.com/bidemewufa/entering_australia_customs_form.pdfIn PDF document text
    • https://s3.amazonaws.com/laradusa/school_letterhead_format.pdfIn PDF document text
    • https://s3.amazonaws.com/sajatofubote/75558766104.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010038.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10038 12460 bytes
SHA-256: b69cfe3c38cc41a9b58e80f054f1d604329127778d2a9a4403c8ffa1c7ddc091
font_01_sfnt_off000128b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128B1 5572 bytes
SHA-256: 196617be74e2a968157aa3587064ea38838eb0c1053b2b481928c6abaff316d3
font_02_sfnt_off00013bc9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13BC9 2040 bytes
SHA-256: 4581f70ecaa3d814ff9ca559f812eb8113c04d19fe2c4502590010fa3c1cf07f
font_03_sfnt_off00014575.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14575 11736 bytes
SHA-256: 44ec15d069af07115e2141eb6330d7921cf90a73cd0b538835c2d0ef21e3a097
font_04_sfnt_off00016d93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16D93 17160 bytes
SHA-256: 8d2c605f2719cd6ae022aab266338bee5abc8c7661220778324e8b3236fb8d96