Malicious PDF — malware analysis report

Static analysis result for SHA-256 78d8f0744ee78afb…

MALICIOUS

PDF

81.7 KB Created: 2021-03-19 18:32:22 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0b2c2a6318480dc37af08db97482a7b9 SHA-1: 90f1ae79e2a8258c97b5c388759bee03203e788a SHA-256: 78d8f0744ee78afbbd98cef59c037306284a3f1982be870536a35d54bf6a190c
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, many of which appear to be part of a link farm designed to improve search engine rankings for specific keywords, such as 'five nights at freddy's 2 apk full android'. The primary URL points to a site that likely hosts malicious content or phishing pages. While no scripts were explicitly extracted, the PDF structure and the presence of numerous external links suggest it's designed to redirect users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://jacksth.ru/wix?keyword=five+nights+at+freddy%2527s+2+apk+full+android
    • https://cdn.sqhk.co/sixitigoxeto/h3E07Ym/storage_analyzer_disk_usage_pro.pdf
    • http://melodabogaso.66ghz.com/prologue_to_the_canterbury_tales_analysis.pdf
    • https://cdn-cms.f-static.net/uploads/4486060/normal_60396d535aae8.pdf
    • https://cdn-cms.f-static.net/uploads/4474752/normal_6025482aebda6.pdf
    • https://cdn.sqhk.co/nozedimasav/nhiSgdA/phoenix_airport_food_covid.pdf
    • https://cdn.sqhk.co/peferitukofa/OnLijBu/javascript_string_format_leading_zeros.pdf
    • https://cdn-cms.f-static.net/uploads/4481994/normal_601db5e98be03.pdf
    • https://static.s123-cdn-static.com/uploads/4368977/normal_5ffc17ab97815.pdf
    • https://cdn.sqhk.co/wodaximewule/4idabhh/alien_shooter_2_the_legend_pc_trainer.pdf
    • https://cdn.sqhk.co/poxirowo/UOgcjbV/49386393701.pdf
    • https://cdn.sqhk.co/vekokoze/jVajdgi/bass_boost_car_audio.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://adc0bc6f-2b4d-4951-bce0-9128d215fa34.filesusr.com/ugd/5ea4d5_b9ce575914e44e13998edd46a36172cd.pdf?index=true
    • https://s3.amazonaws.com/vigevot/alexander_the_great_name_in_urdu.pdf
    • https://72a23b54-95c1-47c0-80d6-f7b1310faeb8.filesusr.com/ugd/65b209_d712893621cb4c4aa2971c800067b674.pdf?index=true
    • https://s3.amazonaws.com/numunenoji/98397686172.pdf
    • https://s3.amazonaws.com/dudigonifu/figurative_language_worksheet_1_ereading.pdf
    • https://s3.amazonaws.com/fajixe/nice_guidelines_preeclampsia.pdf
    • https://70848fb0-0fd0-490a-9360-2ffa38fc212c.filesusr.com/ugd/08e331_9b5436e4035f4c1f884c14c16465cb40.pdf?index=true
    • http://gudekor.rf.gd/66826824234.pdf
    • https://8d537faf-e869-4ed9-a29f-988560fab1dc.filesusr.com/ugd/0cce51_41eba3b4f5874d23bb42e2d591bead18.pdf?index=true
    • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f23e.bin
5e81746eef6f1dc28c04a89a9cdae8260bcd8bdf2b59630af3325837b7659a56
pdf-font-stream PDF embedded font (sfnt) at offset 0xF23E 5532 bytes
font_01_sfnt_off00010526.bin
39f7ca13827d2d283f541732a78cf2398c38b51596bb07371d5d10ecc50ebd71
pdf-font-stream PDF embedded font (sfnt) at offset 0x10526 10972 bytes
font_02_sfnt_off00012aaf.bin
1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361
pdf-font-stream PDF embedded font (sfnt) at offset 0x12AAF 4324 bytes