Malicious PDF — malware analysis report

Static analysis result for SHA-256 be643c69af81c429…

MALICIOUS

PDF

83.1 KB Created: 2021-03-10 03:54:37 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: f9cc330fd2f9efbef88de7bcfc858990 SHA-1: 43eb92a1813b459e411a3d514a72c8122d9a7243 SHA-256: be643c69af81c4295877a5b5f05a051091592bacdb6c05f21b53bf21f2d748d9
146 Risk Score

Malware Insights

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

The PDF contains malformed streams and is flagged by ML classifiers and ClamAV as malicious. It functions as a link farm, directing users to multiple external URLs, including suspicious domains like nipisod.ru and cdn.sqhk.co, which are likely used for phishing or distributing further malware. The presence of embedded URIs and the overall structure suggest an attempt to trick users into visiting malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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
  • 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.
  • 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 https://nipisod.ru/award?keyword=matrix+of+african+proverbs+pdf PDF link annotation
    • https://cdn.sqhk.co/pufojoloz/Ljbifjj/sozesebozemukefez.pdfIn PDF document text
    • https://cdn.sqhk.co/tononapiwaso/vNUYyhd/82500463212.pdfIn PDF document text
    • https://cdn.sqhk.co/sovanoniwuva/HijhffE/plants_vs_zombies_ps4_youtube.pdfIn PDF document text
    • http://storeyou.store/how_to_reset_asus_router_account_password21c2k.pdfIn PDF document text
    • http://lady-bug.club/47740169293r90ma.pdfIn PDF document text
    • https://jixepelisu.weebly.com/uploads/1/3/2/6/132695865/mulemitutesoj-sidepadaruxadok-gonegud-ludezajo.pdfIn PDF document text
    • https://nisudine.weebly.com/uploads/1/3/1/4/131454656/botogosakivam-sulololumefuj-joxixoxu-lumamedateral.pdfIn PDF document text
    • http://uspehdnyaaxyz.xyz/jvc_kd-x320bts_color_changejeebb.pdfIn PDF document text
    • https://pepizowa.weebly.com/uploads/1/3/2/7/132711999/6035022.pdfIn PDF document text
    • http://khareedforosh.com/mindfulness_coloring_book_for_adultsr9rfi.pdfIn PDF document text
    • http://support-copyrighthelpservice-about.com/why_per_capita_income_is_not_a_good_indicatorpyj46.pdfIn PDF document text
    • https://rokawutavepuma.weebly.com/uploads/1/3/0/7/130776645/nonarowosigirosapazu.pdfIn PDF document text
    • https://cdn.sqhk.co/sobekalob/hd2jjjf/kigofazubosixamudusam.pdfIn PDF document text
    • http://nipokaxa.getenjoyment.net/relefebunu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://s3.amazonaws.com/sosupejuxofedo/43751435867.pdfIn PDF document text
    • https://s3.amazonaws.com/gonima/diccionario_biblico_nelson.pdfIn PDF document text
    • http://siniligavaxuvul.onlinewebshop.net/cisco_ccna_200-301_cheat_sheet__quick_study_guide.pdfIn PDF document text
    • http://tososite.onlinewebshop.net/how_to_set_time_and_date_on_vtech_cordless_phone.pdfIn PDF document text
    • https://s3.amazonaws.com/ziwuvijevo/4292294379.pdfIn PDF document text
    • https://s3.amazonaws.com/tazopaju/how_to_clean_printhead_on_epson_workforce_3640.pdfIn PDF document text
    • https://s3.amazonaws.com/tiluwisulepam/77833916637.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e639.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE639 5180 bytes
SHA-256: f0559895ecaedce98bb70459a667c1a0f68ef8517a7d19df478081b6c1408443
font_01_sfnt_off0000f7eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7EB 10376 bytes
SHA-256: 2e8eb34e248154ff311fdd2eeda6415b77ec76c5b4a55f46fdf705f0e334cbb1
font_02_sfnt_off00011bb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BB2 16164 bytes
SHA-256: f469c5aa689aa4c1965481b78cfaebbf1c3ebdad2306c7067134b7b4aaa0addd
font_03_sfnt_off000130ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130AB 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333