Malicious PDF — malware analysis report

Static analysis result for SHA-256 82ba311c47ec9396…

MALICIOUS

PDF

79.5 KB Created: 2021-09-15 13:47:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: d28e6dce5400a674c8a204dbfbf17b9f SHA-1: ef6b842c02de6f2124c68843abae367260a9755b SHA-256: 82ba311c47ec9396ff16dbca5daebe151248b8041cdd3a6c0b107e4769a26d72
126 Risk Score

Malware Insights

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

The file was detected by ClamAV as Pdf.Phishing.Trojan and an ML classifier returned a high probability of maliciousness. It contains numerous embedded URLs, many of which are hosted on disposable domains and appear to be part of a link farm, suggesting a phishing or malware distribution scheme. The PDF structure itself is also flagged for containing duplicate objects, which can be used to obfuscate malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://oniceh.ru/uplcv?utm_term=download+text+me+apk+latest+version PDF link annotation
    • https://cordovajewelry.com/images/file/98675855465.pdfIn PDF document text
    • https://holocaustresearch.pl/nowy/photo/file/netazegidova.pdfIn PDF document text
    • https://festacontinua.it/public/file/52880033846.pdfIn PDF document text
    • http://nj-rshb.com/v15/Upload/file/2021932230118635.pdfIn PDF document text
    • http://lapempi.nl/ckfinder/userfiles/files/53383881200.pdfIn PDF document text
    • https://dolupin.com/calisma2/files/uploads/57020415562.pdfIn PDF document text
    • http://loaamtran.vn/files/usersfiles/files/9910292581.pdfIn PDF document text
    • http://stainless-faucet.com/uploads/htmlupload/files/pegixusobesevutemedizul.pdfIn PDF document text
    • https://adci.vn/data/upload/file/daporukunodogufizojuwime.pdfIn PDF document text
    • http://fxlcd.com/upload/file/zerolurodonepoxufobur.pdfIn PDF document text
    • https://goldmenu.com/userfiles/file/siravirisimerizokasise.pdfIn PDF document text
    • http://asliev.coco1490.com/upload/file_folder/file/90744580690.pdfIn PDF document text
    • https://rmdschoolandcollege.com/wp-content/plugins/super-forms/uploads/php/files/9ee2da79de5ef8be1097ecf0d4b8f7c3/waxixumidifiwaliz.pdfIn PDF document text
    • https://songhongresort.com/img/files/4341932709.pdfIn PDF document text
    • http://ntvietnga.com/upload/files/28356727493.pdfIn PDF document text
    • https://hsiaoying.com/userfiles/file/xebupexex.pdfIn PDF document text
    • http://namadagaskare.ru/ckfinder/userfiles/files/zabiredasipudeje.pdfIn PDF document text
    • http://cameranichietsu.com/luutru/files/75354308129.pdfIn PDF document text
    • https://quangcaowebsite.xemlaco.com/uploads/files/vexozodeguponodakofeme.pdfIn PDF document text
    • http://mentor-tutor.com/newGroserLikeProject/uploads/files/robakis.pdfIn PDF document text
    • 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_off0000d272.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD272 10900 bytes
SHA-256: ef0966c2858ccc229e1012bc4b717dc6a3d01cdebce186f143cc693609ea0b7f
font_01_sfnt_off0000ebb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBB9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000103cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103CB 17736 bytes
SHA-256: 5d3eb7a76335e8e9556db5199ef91aa606e59405bc87199fafd5093a13742694