Malicious PDF — malware analysis report

Static analysis result for SHA-256 78f2f6a115d85475…

MALICIOUS

PDF

82.7 KB Created: 2021-09-10 15:05:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: 7f0c00086e8b18f5ff5821c5cf4343f8 SHA-1: b4904fcf89321492fc2a4b951e389eda97bd1e61 SHA-256: 78f2f6a115d854755878f8169bc1eed5948c1fc35455dd4976a1512f5588fbc8
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple external links, many of which point to other PDF files hosted on various domains. The presence of a 'download button' heuristic and the ML classifier's high confidence score indicate a malicious intent, likely to trick users into downloading further malicious content. The ClamAV detection further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • 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.
  • 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://alusol-kw.com/ckfinder/userfiles/files/30513426759.pdf In PDF document text
    • http://scherzerpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/sijigira.pdfIn PDF document text
    • https://santchavarabed.in/ckfinder/userfiles/files/raxofu.pdfIn PDF document text
    • http://nuitsdartistes.eu/images/file/zowasuxupeni.pdfIn PDF document text
    • http://designbyjoseph.com/uploads/File/40877748740.pdfIn PDF document text
    • https://envida-nieuws.nl/bsb_website/upload_fck/file/92436651985.pdfIn PDF document text
    • http://www.enredmail.com/templates/files/idCliente_/file/25766788915.pdfIn PDF document text
    • https://www.hemingway.bg/app/templates/js/ckfinder/userfiles/files/38551165966.pdfIn PDF document text
    • http://gldbirdgel.com/user_img/files/polumufirelikamed.pdfIn PDF document text
    • http://streetnn.ru/data/upload/ck/files/lujud.pdfIn PDF document text
    • https://kamhosting.nl/ckfinder/userfiles/files/biwenazopoma.pdfIn PDF document text
    • http://exima.kr/userData/board/file/jajodasased.pdfIn PDF document text
    • http://cheers-gifts.com/userfiles/fogerabepositulavad.pdfIn PDF document text
    • https://qualitygums.com/userfiles/file/96084333081.pdfIn PDF document text
    • http://powerfalcon.net/uppic/files/93236416319.pdfIn PDF document text
    • http://mwflower.com/upimagesfile///96720630292.pdfIn PDF document text
    • https://ratosatu.com/contents/files/89947106881.pdfIn PDF document text
    • http://bladensburg.abwingsmd.com/uploads/files/25917668883.pdfIn PDF document text
    • http://sahrugs.com/userfiles/file/21443294901.pdfIn PDF document text
    • https://linhquan-group.com/upload/ck/files/zulalosuwutud.pdfIn PDF document text
    • https://myvideoclasses.com/ci/userfiles/files/xonimuwuxonaxa.pdfIn PDF document text
    • http://grawerlik.pl/userfiles/file/88623499272.pdfIn PDF document text
    • https://careerexpo.alljobsinliberia.com/ckfinder/userfiles/files/71305081278.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=acrobat+remove+passwordPDF 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_off0000de10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE10 10708 bytes
SHA-256: 19907e491540024465d0f033b368a02481f1a323ff6265009069907f635d0b84
font_01_sfnt_off0000f691.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF691 18348 bytes
SHA-256: 0739c105f7cc7024de75baddf7333a1db04fa582407bcacb7ece9701c04bb273
font_02_sfnt_off0001251d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1251D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1