Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5079bb702ca0421…

MALICIOUS

PDF

98.2 KB Created: 2021-03-10 23:19:09 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: 400e6d1acfbf45925cd28e81b1edb599 SHA-1: 24c4ecaa71aa1406d1f97244d0d99f8473156557 SHA-256: c5079bb702ca04213467acf9be3fa80279fd4d28415cea6fcddc7ae57e94252d
176 Risk Score

Malware Insights

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

The PDF contains a malformed exploit stream and embeds a URL that appears to be part of a link farm, suggesting malicious intent. The ML classifier and ClamAV detection strongly indicate this is a malicious PDF, likely used for phishing or to deliver a second-stage payload via the embedded URL.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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://jacksth.ru/aws?utm_term=the+visual+basic+.net+programming+language+pdf PDF link annotation
    • https://cdn.sqhk.co/fujonexa/OhibTif/survivalcraft_2_apk_indir.pdfIn PDF document text
    • https://cdn.sqhk.co/baruduwege/hVzshfi/vulijuxakakaguwawipug.pdfIn PDF document text
    • http://dazemuwemez.22web.org/54334894419.pdfIn PDF document text
    • https://cdn.sqhk.co/bisulalu/he3hiKS/skyblock_addons_mod_1._16._1.pdfIn PDF document text
    • https://cdn.sqhk.co/zovaratigu/aucMhgf/faraway_puzzle_escape_level_20_notes.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/a6fd6953-f201-45d9-96a6-d085fff7af13/71625541939.pdfIn PDF document text
    • https://s3.amazonaws.com/lotibabakuj/97923724843.pdfIn PDF document text
    • https://s3.amazonaws.com/besafefaf/rawitilofupe.pdfIn PDF document text
    • http://patuwovoparivi.rf.gd/rinutovemedifawudugibes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6ef6ed21-eb3c-40a2-97aa-ccf28709a07f/81673766680.pdfIn PDF document text
    • https://s3.amazonaws.com/tixedujegibex/1276178758.pdfIn PDF document text
    • https://s3.amazonaws.com/fajujiju/raw_cabbage_nutrition_information.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ac2221ca-53c9-41d6-a157-71f9f4ba2e13/16706701860.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1f04789e-c1f4-40f1-ae8d-7da8eb3861bc/66220726784.pdfIn PDF document text
    • http://metivatozu.epizy.com/python_selenium_chromedriver_file.pdfIn PDF document text
    • https://s3.amazonaws.com/tutapaxi/59365783204.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/77f324fc-5a95-4833-89ce-cd6bf88e393f/66084855807.pdfIn PDF document text
    • http://vekifaxofezawe.epizy.com/how_to_read_z_table_for_confidence_interval.pdfIn PDF document text
    • http://xadupozitolewoj.epizy.com/trane_rtac_300_chiller_manual.pdfIn PDF document text
    • https://a2876ee3-c470-454a-91e2-e108d831033a.filesusr.com/ugd/e8dba5_8f6ebc812d724448afa9f3012cbbe9f7.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/491a4f45-ed52-4a13-abf2-16b71ffe7742/the_lover_marguerite_duras_epub_download.pdfIn PDF document text
    • https://27a83426-c768-4525-a63d-b5b732cca755.filesusr.com/ugd/28b3f7_ed4c9d0d548f4007b6210bfccd1ac39f.pdf?index=trueIn PDF document text
    • https://2e81f42f-67f9-46a9-89e2-a5f3ab3b03ee.filesusr.com/ugd/f138f5_6ab72793dd044c29b0ea914e59191030.pdf?index=trueIn 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011b8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B8B 4016 bytes
SHA-256: 403effb9c3c639814c148cac1e498e74bf8eb2f2dc2f9263a666fdeaf4abcb47
font_01_sfnt_off000129b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129B8 5752 bytes
SHA-256: 95343336c59e57830365bdfa0757edf4acbd17f1c903b2f5434093af9e03b961
font_02_sfnt_off00013d1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D1E 12008 bytes
SHA-256: 6acb6f1bef99b52df659436ea4722f641822f2861bd01089546e210d848f38db
font_03_sfnt_off0001656d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1656D 16164 bytes
SHA-256: d781c508aaf473e50263a6aabc3f4161b7fa10724c54bb8d35addee38a7f1c44