Malicious PDF — malware analysis report

Static analysis result for SHA-256 65a136f1e3ffe30b…

MALICIOUS

PDF

82.9 KB Created: 2021-09-15 11:16:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: b1a983c958cba1c6a811390549f0f7ee SHA-1: 3f9285f94b9e5c21d4e09ca52ade15e94db227ed SHA-256: 65a136f1e3ffe30b246d9f3c5f20466e773d8290ffbdce1d0bf9456ceb6ea677
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected as a malicious PDF by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to potentially malicious domains, suggesting a link farm or phishing lure. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating the PDF is designed to distribute links from disposable hosting. No scripts were extracted, but the presence of multiple external URIs points to an attack pattern involving directing users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://tianlanlawyer.com/filespath/files/20210912060620.pdf In PDF document text
    • http://aci-immobilier-douai.fr/userfiles/files/fawodumivamin.pdfIn PDF document text
    • http://splhardware.com/UploadFile/file/2021091221463973499.pdfIn PDF document text
    • https://www.shipgo17.com/plugin/ckeditor/ckfinder/userfiles/files/wesemonazopoluv.pdfIn PDF document text
    • http://movesearchesuk.com/userfiles/file/tomuvewufisirugaxeke.pdfIn PDF document text
    • http://tdvvietnam.vn/webroot/img/files/zusanidefipep.pdfIn PDF document text
    • http://indagosrl.it/userfiles/files/88736260814.pdfIn PDF document text
    • http://alompar.hu/uploads/content_files/files/29071191469.pdfIn PDF document text
    • http://packamate.com/userfiles/45439572211.pdfIn PDF document text
    • http://toflight.mobi/attachment/ckeditor/files/69604a50b912198eec17676b626f3148.pdfIn PDF document text
    • https://bhiringisamsankalimandir.org/ckfinder/userfiles/files/98893754809.pdfIn PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e099a74c00---piriramelaxatoridi.pdfIn PDF document text
    • https://sfeerweter.nl/userfiles/files/sojefuwupakomovurapo.pdfIn PDF document text
    • https://pasarantogel2.com/contents/files/zupolebosijazixepuwu.pdfIn PDF document text
    • https://www.profiemg.cz/upload/ck/files/86745505082.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613b5f076945b---7181523157.pdfIn PDF document text
    • https://fsbulletsandbrass.com/userfiles/files/69267160796.pdfIn PDF document text
    • http://touristclub.in/userfiles/file/tidetuwe.pdfIn PDF document text
    • https://gastriklandsbf.se/UserFiles/files/12680810886.pdfIn PDF document text
    • https://hunglivet.com/uploads/files/202109041528156763.pdfIn PDF document text
    • http://qiuyutv.com/userfiles/files/20210907121819.pdfIn PDF document text
    • https://loonbedrijfschimmel.nl/userfiles/files/boxukisuzekoxigenalovibe.pdfIn PDF document text
    • http://werder-ritter.de/UserFiles/File/79079261036.pdfIn PDF document text
    • http://bjqyms.com/filespath/files/20210903140152.pdfIn PDF document text
    • http://bulk-supplies.com/userfiles/file/sisoloxalekujexejoleguw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=how+to+fix+play+store+downloading+problemPDF 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_off0000dc5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC5B 18388 bytes
SHA-256: 330163acfc62c635b53c41b8e6fd3287a3b4c9a79e5c8674a63953d9f66ddc7f
font_01_sfnt_off00010be6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BE6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000123fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123FD 11272 bytes
SHA-256: be1b1c539512bd0336af3a27a13b163d1f943a2afc5ef53f19008317a3282cac