Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9c533aaefd50cd6…

MALICIOUS

PDF

77.5 KB Created: 2021-09-20 11:22:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: b7daeb48084798fe65eca3ac677ca3df SHA-1: a5d339117e6bc159ec0bd43a6da7abcb311ef36c SHA-256: c9c533aaefd50cd65f4b54946e325c17cfbd43cbb8567ab1fab674790c4a3403
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating embedded JavaScript and a link farm structure. The presence of external URIs and a 'download button' heuristic suggests a phishing or malware distribution attempt. The embedded JavaScript, while not directly executable in this context, is a common component in malicious PDFs for initiating further malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://infrive.ru/uplcv?utm_term=beta+pubg+download+apk PDF link annotation
    • http://phfamilyrestaurant.com/uploads/files/89229782452.pdfIn PDF document text
    • https://virtualpulse.eu/UserFiles/file/52559935992.pdfIn PDF document text
    • http://libron.pl/fckupload/assets/file/xudum.pdfIn PDF document text
    • http://osheamaloneynylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/megefexosemiz.pdfIn PDF document text
    • https://majubesar.com/contents/files/keraxixewoxokur.pdfIn PDF document text
    • http://angel-conference.org/upload_fck/file/2021-9-12/20210912222632957586.pdfIn PDF document text
    • http://juentai.com/userfiles/files/moduto.pdfIn PDF document text
    • https://www.studioline.ie/ckfinder/userfiles/files/48615655490.pdfIn PDF document text
    • http://busangh.com/attfile/fckimg/file///20210910205130_385078467.pdfIn PDF document text
    • http://xn--h1aeekk.xn--p1ai/files/file/tanonegubudebonunewiram.pdfIn PDF document text
    • http://geasit.it/userfiles/files/gixos.pdfIn PDF document text
    • http://euhoca.com/js/ckfinder/userfiles/files/95858438008.pdfIn PDF document text
    • http://streathamtaxi.com/survey/userfiles/files/41061523314.pdfIn PDF document text
    • http://tayles.com/uploaded/vegakoxodowurenizof.pdfIn PDF document text
    • https://cmflower-kkc.com/ckfinder/userfiles/files/18670603223.pdfIn PDF document text
    • https://tnmkor.com/FileData/ckfinder/files/20210918_C9B1CB36BEF49E56.pdfIn PDF document text
    • http://murasakijr.com/uploads/files/luvizikovetadi.pdfIn PDF document text
    • https://anbuadidravidarmatrimony.com/ckfinder/userfiles/files/fozipobigesivuno.pdfIn PDF document text
    • https://grupahatak.pl/admin/_fck_files/file/90888889382.pdfIn PDF document text
    • http://7m-shop.com/userfiles/file/77073574864.pdfIn PDF document text
    • https://bodymason.com/user_uploads/files/80501481693.pdfIn PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a873b841ab---86787883416.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613327573f34d---xarigalu.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_off0000c8fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8FE 10680 bytes
SHA-256: 2b9379089204bec001db0a37d2229fa456ea55f3047f393e93947b3ea269e2d1
font_01_sfnt_off0000e13d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE13D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f94f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF94F 18124 bytes
SHA-256: d37f55fdf7d20bdbbb88ba2966783d90f5b87a0b33dc60875b7d348ed98ec9e1