Malicious PDF — malware analysis report

Static analysis result for SHA-256 316e9fc0b0e701ea…

MALICIOUS

PDF

81.9 KB Created: 2021-09-17 15:46:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 10626de6b770cfc1dd88f9798c36d518 SHA-1: ab964cda577c3394d2e401d7bd5088a73dc22963 SHA-256: 316e9fc0b0e701ea3e780b2dd6cada575b8fa29b363a9f6bb76043b73c3e0321
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple heuristic firings indicating malicious intent, including random and disposable link farms pointing to external PDF files. The ML classifier and ClamAV detection strongly suggest this is a phishing or malware distribution attempt. While no scripts were explicitly extracted, the PDF structure and embedded links are designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://chcial.ru/uplcv?utm_term=how+many+days+can+you+keep+chicken+in+the+fridge PDF link annotation
    • https://agentcctv.com/userfiles/file/talidesijodeguzuwir.pdfIn PDF document text
    • https://gibidesign.com/fckfiles/file/rezukixugizawumik.pdfIn PDF document text
    • http://lawcab.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614139c0022d2---simolafez.pdfIn PDF document text
    • http://baoveantam.org/upload/files/fimemagejofadafepi.pdfIn PDF document text
    • http://hyeminshop.com/DATA/files/jujibunebijotuwaderuris.pdfIn PDF document text
    • https://detskeihriska.eu/ckfinder/userfiles/files/86939964522.pdfIn PDF document text
    • http://xn--djr00fsyfv0o5qgy9u.net/filespath/files/20210908210420.pdfIn PDF document text
    • http://resheto.ru/users_images/fck/file/wonufirulul.pdfIn PDF document text
    • http://buydecor.ru/uploads/files/79640500239.pdfIn PDF document text
    • http://xn----ctbguteehkho5h.xn--p1ai/ckfinder/userfiles/files/8959593486.pdfIn PDF document text
    • https://greenbins.ca/ckfinder/userfiles/files/71290458457.pdfIn PDF document text
    • https://eslms.com/userfiles/file/vokoruvowulojezujusi.pdfIn PDF document text
    • https://greenfins-thailand.org/uploads/file/35424361851.pdfIn PDF document text
    • http://carraracucinecomponibilitrapani.it/userfiles/files/denav.pdfIn PDF document text
    • http://hicoweld.com/shop/fck_file/file/22054394120.pdfIn PDF document text
    • http://xn--80aafkatcapceshpicpg3h.xn--p1ai/pict/file/46263218888.pdfIn PDF document text
    • http://vwtint.com/userData/board/file/80373949271.pdfIn PDF document text
    • http://chongthamnguoc.vn/img/files/36872120854.pdfIn PDF document text
    • https://bikidi.com/UpFiles/WebEditorFiles/file/86165558116.pdfIn PDF document text
    • https://twinscooking.nl/twins/userfiles/file/64291524800.pdfIn PDF document text
    • https://xn--80adj7cxa.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/29d813c668f826e8a6a9b4e7d2c1f70f/66926970000.pdfIn PDF document text
    • http://toyotaquangninh.org/data/dulieu/files/ruwoboweturubegaguvuresup.pdfIn PDF document text
    • http://www.almansori-ye.com/almansorifiles/files/35624236244.pdfIn PDF document text
    • http://akwarella.pl/user_uploads/file/37912234219.pdfIn PDF document text
    • http://fortwashington.abwingsmd.com/uploads/files/mebimudizizulabimolenenob.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_off0000d9ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9AE 17584 bytes
SHA-256: 63e7bed4c4fb3b4388c407c2cea9e77b8e8d7c02402f852491fa456f7773cb32
font_01_sfnt_off000106f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106F6 11404 bytes
SHA-256: 0c056dbeaf7212220dde9539e5c05c667948cf5e10209c11f1c423499d3adb22
font_02_sfnt_off0001218e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1218E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1