Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b16f6d6142a68ac…

MALICIOUS

PDF

71.8 KB Created: 2021-04-07 10:31:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1ffd4178e4c12cd5743d1cb1b693a0cb SHA-1: d577a17b31bd8678c2370cfa3a3da5ae315b6f6d SHA-256: 1b16f6d6142a68acc49aa24ac90e185f03023004da1815dff8651617cc1c8eaf
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, as indicated by the PDF_SEO_LINK_FARM heuristic, suggesting a link farm or phishing attempt. The ML classifier and ClamAV detection strongly indicate maliciousness. While no scripts were directly extracted, the presence of external URIs and the nature of the heuristics point towards a phishing or malicious redirection attack, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 5

  • 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.
  • 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://crophysi.ru/strik?utm_term=irobot+roomba+i7%252B+stores
    • http://familyit.pro/lodagavumadinadifewilevokjmn2.pdf
    • https://static.s123-cdn-static.com/uploads/4474739/normal_5ff4e1ce00295.pdf
    • https://cdn-cms.f-static.net/uploads/4465949/normal_6036490281257.pdf
    • https://cdn-cms.f-static.net/uploads/4424027/normal_5fe72c4d6f6e8.pdf
    • http://rollernefrit.xyz/the_blue_book_is_used_by_disability_determination_servicesdkkar.pdf
    • https://cdn-cms.f-static.net/uploads/4419437/normal_5fe6c56fcd1ed.pdf
    • https://cdn-cms.f-static.net/uploads/4498392/normal_603582496b97d.pdf
    • http://katermore.ru/supuvoxumitomelo2qnxm.pdf
    • https://cdn.sqhk.co/ketifoseja/fkjfdib/58251575737.pdf
    • https://cdn.sqhk.co/bomumuxa/6ggfXC3/39897873464.pdf
    • https://static.s123-cdn-static.com/uploads/4421061/normal_5ffe4b03ee358.pdf
    • https://cdn-cms.f-static.net/uploads/4387819/normal_5fd7cf232be98.pdf
    • https://cdn.sqhk.co/xurazegoba/Sicjjhd/sotedagizaligovuxewito.pdf
    • https://cdn-cms.f-static.net/uploads/4392649/normal_606a45d4846df.pdf
    • http://chaptejvxz.fun/what_are_the_2_reactants_in_aerobic_respiration60o4t.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/xupovobejanam/do_i_have_acne_or_just_spots.pdf
    • https://de461234-8179-4892-b46d-67dc01ae00af.filesusr.com/ugd/69bbc5_e630f5d4449c4fa7afb2eab410df716b.pdf?index=true
    • https://3ff4c494-4984-418a-b709-7a5c611cca0a.filesusr.com/ugd/adbee0_a6b5c7e7c083420ab50c1ae400485f25.pdf?index=true
    • https://s3.amazonaws.com/zetubakuz/femot.pdf
    • https://aca292c6-a3ee-4c96-b4c9-db15c8eca1b9.filesusr.com/ugd/cd1d52_b4c3ebfd83be4f7cb4358fcc1afbecae.pdf?index=true
    • https://s3.amazonaws.com/jesidofefe/what_does_the_veil_in_the_ministers_black_veil_symbolize.pdf
    • https://f26e6bca-ce10-4524-9610-ed5ef7c8d48b.filesusr.com/ugd/ac8c68_45acea6515a947c198048c6abbae9ddb.pdf?index=true
    • https://s3.amazonaws.com/nerugiraxura/44075796172.pdf
    • https://s3.amazonaws.com/fakuguvil/sedirorixedulibin.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_off0000dc4c.bin
ac21a688c666927c503d1ca812861b24b34e05d7f97c7870ab8b5699f7fda6d7
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC4C 4956 bytes
font_01_sfnt_off0000ed10.bin
9ed5840050c87ca4c4d0124b3861c0e459df0e5f8ade2eaac02cdda597e6dd22
pdf-font-stream PDF embedded font (sfnt) at offset 0xED10 10596 bytes