Malicious PDF — malware analysis report

Static analysis result for SHA-256 28ffaac06322217a…

MALICIOUS

PDF

75.9 KB Created: 2021-04-15 04:53:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fee479bc61338b56eadf3aaa607b3eb9 SHA-1: 21d9122d1606869151a87eef619dd302134ed0b2 SHA-256: 28ffaac06322217a7c47019a0cd1e2c6d1ae9e95618a9c96425caa91719d2f55
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including ClamAV and an ML classifier, indicating malicious content. The PDF_SEO_LINK_FARM heuristic suggests it contains a large number of external links, with one prominent URL being https://pelibifir.ru/strik?utm_term=2008+jeep+wrangler+for+sale+2+door. This indicates a likely phishing or malware distribution attempt disguised as a link aggregator.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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=2008+jeep+wrangler+for+sale+2+door
    • http://laitlabs.pro/how_to_draw_a_face_from_3_4_viewerdy7.pdf
    • http://iciko.xyz/86519171151l4zor.pdf
    • https://cdn-cms.f-static.net/uploads/4501989/normal_602925cf13b80.pdf
    • https://jesisime.weebly.com/uploads/1/3/4/8/134886507/7963632.pdf
    • https://tobalewaluwe.weebly.com/uploads/1/3/4/4/134437424/5325485.pdf
    • http://romotogez.22web.org/video_converter_for_android_2._3._5.pdf
    • https://nulakumoxuguv.weebly.com/uploads/1/3/1/8/131871970/razakexi-wawanana-mesofeserusul-bebimumix.pdf
    • https://cdn-cms.f-static.net/uploads/4455405/normal_601d0596a10b7.pdf
    • https://static.s123-cdn-static.com/uploads/4408596/normal_5feccd8836c2e.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://0298dc5a-7924-4276-8279-06452a5288da.filesusr.com/ugd/b30cf0_ee5f3813f54c4553baad679babaa18f6.pdf?index=true
    • http://volififujuwimi.epizy.com/vizio_sb3851-c0_38-inch_5.1_channel_sound_bar.pdf
    • http://tojederetesez.epizy.com/katekuxoresiwilumim.pdf
    • https://9d349da1-218b-4b59-9e37-2a90cab56d40.filesusr.com/ugd/de9003_b6810b4251a342f69efc991e948e26ca.pdf?index=true
    • https://e055bcc9-c4f1-4c6c-8dcb-0912bf54750f.filesusr.com/ugd/b4a829_e03a4d26ee6e47948aabcc86d1914969.pdf?index=true
    • http://memenusaduso.rf.gd/70941395966.pdf
    • http://bemujamo.rf.gd/anticorpos_antinucleares.pdf
    • http://sevaguv.rf.gd/samsung_corporate_identity_manual.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_off0000ea26.bin
c3d50a7b149f10f57bfba0f729dbcc9c57e9c1ffd6033b8a615ae709bc45974d
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA26 5752 bytes
font_01_sfnt_off0000fde3.bin
428dfce452815949e5d833408753127c234cecc40113bfc43e2f11a798ab4c54
pdf-font-stream PDF embedded font (sfnt) at offset 0xFDE3 10776 bytes