Malicious PDF — malware analysis report

Static analysis result for SHA-256 3ef90ad08e4f31a0…

MALICIOUS

PDF

74.9 KB Created: 2021-09-14 13:34:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: 4f31db20a0ca033326714985abf258fd SHA-1: 0497161fbbcf86019b1df3c718d3155b4e57242c SHA-256: 3ef90ad08e4f31a049afacb184bfb12615a8660586d07693bff7d460b2021dd5
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to suspicious domains and are flagged as part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with common phishing lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://casadko.fr/userfiles/file/46049674376.pdf In PDF document text
    • http://phutungtdc.com/upload/files/gidalajeduf.pdfIn PDF document text
    • https://sadhankendra.org/erc/media/65456820189.pdfIn PDF document text
    • http://hkxhjfc.ltd/uploads/files/20210914175747.pdfIn PDF document text
    • http://giftboxvietthuy.com/upload/ck/files/47971048998.pdfIn PDF document text
    • http://studiotecnicofrisoli.com/userfiles/files/noxefi.pdfIn PDF document text
    • https://farmaciasacoor.com/site/upload/file/54134154474.pdfIn PDF document text
    • http://myucpb.com/userfiles/file/95801990409.pdfIn PDF document text
    • https://conexusinternational.com/ckfinder/userfiles/file/93880289293.pdfIn PDF document text
    • http://honyi.tw/ckfinder/userfiles/file/39162668889.pdfIn PDF document text
    • https://guptajimarriagebureau.com/userfiles/file/72976950358.pdfIn PDF document text
    • https://rainbowfurnitures.com/files/files/67525398777.pdfIn PDF document text
    • https://sunnyrosesschool.com/userfiles/file/19674490530.pdfIn PDF document text
    • https://invest.pl/userfiles/file/91583921645.pdfIn PDF document text
    • http://valentine.tutaylamhet.com/storage/ckfinder/files/puxifoxiwikos.pdfIn PDF document text
    • https://weilaimachinery.com/userfiles/files/61253992725.pdfIn PDF document text
    • http://thehedgerowchronicles.com/ckfinder/userfiles/files/farujilemomikafabe.pdfIn PDF document text
    • https://www.tratedu.net/ssss2018/assets/143ad273/ckfinder/core/connector/php/upload/userfiles/files/20f5dc9292b94511a078305a8f183602.pdfIn PDF document text
    • http://ticketsperiodico.com/galeria/files/femelezumikufirupot.pdfIn PDF document text
    • https://uclerbaklava.com/resources/file/96118122515.pdfIn PDF document text
    • http://smartpaintingplus.com/userfiles/files/4992942574.pdfIn PDF document text
    • https://businessincasey.com.au/application/third_party/ckfinder/userfiles/files/mepaxudasuwokito.pdfIn PDF document text
    • http://teplolux72.ru/upload/file/jidatu.pdfIn PDF document text
    • https://hglobaltourb2c.com/FileData/ckfinder/files/20210913_D7F26755D2B5E97A.pdfIn PDF document text
    • http://test-immo.com/file/48343714331.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=stolen+lucy+christopher+pdfPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bca4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBCA4 10844 bytes
SHA-256: 1573503818359feed27cfdf0a2ebbfce96e51d08af55dcf1a75ab6e849913e68
font_01_sfnt_off0000d595.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD595 18540 bytes
SHA-256: 2dad1db2f24dc411192348660d9e692f72f70333fa2ecedde618db645238a0cd
font_02_sfnt_off0001060f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1060F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1