Malicious PDF — malware analysis report

Static analysis result for SHA-256 0437b3bde3cb7775…

MALICIOUS

PDF

78.5 KB Created: 2021-04-02 22:42:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 16b8bb1b389702902ba89707f96dcf91 SHA-1: 26d48fceb8e5427962f9b560cbf2448e553c6b49 SHA-256: 0437b3bde3cb7775e33a831b805593d23d4c8ca38aa3c199c40ab44945c131d9
96 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The document body, though heavily obfuscated, contains text related to 'wkhtmltopdf' and a URL that appears to be a lure for phishing or malware distribution. The presence of embedded URLs, particularly the one pointing to 'pelibifir.ru', strongly suggests an attempt to redirect the user to a malicious site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 4

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://pelibifir.ru/strik?utm_term=how+many+hours+is+a+miller+bobcat+good+for
    • https://static.s123-cdn-static.com/uploads/4392470/normal_5fece8fc52d1d.pdf
    • http://demask.fun/mosinem73lqf.pdf
    • https://static.s123-cdn-static.com/uploads/4387825/normal_5ff2dd035a982.pdf
    • http://natfreshik.fun/introduction_to_computer_applicationsnc1cn.pdf
    • http://hookup153.online/who_is_the_strongest_gods_of_destructioncsvpv.pdf
    • http://ruszaimclub.ru/sufefejonofighb.pdf
    • https://cdn-cms.f-static.net/uploads/4496014/normal_5fd34f8a83f00.pdf
    • http://feldhaus-klinker-plitka.ru/93663432111yfm06.pdf
    • https://cdn-cms.f-static.net/uploads/4481280/normal_600dc268bf0d4.pdf
    • https://cdn-cms.f-static.net/uploads/4446162/normal_5fd1617bb00af.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/kaxukok/overwatch_hanzo_aim_guide.pdf
    • https://uploads.strikinglycdn.com/files/9c83a566-5bdc-4dce-8e81-76ba5bca6491/15381215446.pdf
    • https://uploads.strikinglycdn.com/files/b4a8f70e-d402-4ded-992b-69b9bdbb619d/natibaloluxenasudopolen.pdf
    • https://uploads.strikinglycdn.com/files/5de586fd-5771-4805-abbc-2ca18c4e45a9/how_to_setup_hp_deskjet_3050a_j611_wireless.pdf
    • https://uploads.strikinglycdn.com/files/084e7f81-40b1-47fb-b2e8-b4451d5ed7c3/administracion_de_medicamentos_via_rectal.pdf
    • https://s3.amazonaws.com/vobuturinivi/55706208944.pdf
    • https://s3.amazonaws.com/tobito/34319428653.pdf
    • https://s3.amazonaws.com/muvojugejoxip/how_to_type_power_sign_on_keyboard.pdf
    • https://s3.amazonaws.com/fomaralunex/55124486015.pdf
    • https://s3.amazonaws.com/tinivukedeta/82978555042.pdf
    • https://s3.amazonaws.com/tawovojo/entry_form_template_excel.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f476.bin
23e72bb4a2a398819578ce101a4e6efdb46a11f5416e759ec33cbe791f480ea4
pdf-font-stream PDF embedded font (sfnt) at offset 0xF476 5728 bytes
font_01_sfnt_off000107d8.bin
3cb68344591904e18d0de5af6dc5a831a54cdec933fb9b4cd896253c7360c25b
pdf-font-stream PDF embedded font (sfnt) at offset 0x107D8 10672 bytes