Malicious PDF — malware analysis report

Static analysis result for SHA-256 81eee03fab36814b…

MALICIOUS

PDF

89.6 KB Created: 2021-07-27 16:53:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 1673284ca7c14255ef1d7e35e720258b SHA-1: 216d0ee7091c5ccda93c03f6a65e81d8ad5786a8 SHA-256: 81eee03fab36814bf5f90ce17f75b52c00a6fea0fbefe38d48117025cfcc0cc3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample was identified as malicious by ML classifiers and ClamAV, flagging it as a phishing trojan. It contains numerous embedded URLs, many pointing to compromised or disposable hosting, forming a link farm. The primary function appears to be redirecting users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://skpizzasubs.com/uploads/files/mujofotikikeson.pdf In PDF document text
    • http://pferdefreunde-brueckenhof.de/sites/default/files/userfiles/file/mobew.pdfIn PDF document text
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/85dcb27fbf1855548628335357185e84/66634168086.pdfIn PDF document text
    • http://bbpcosmetics.com/admin/upFiles/2021-5/file/lusovebo.pdfIn PDF document text
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/16081e7ca9ce09---vanokipozegezodobixegel.pdfIn PDF document text
    • http://younewstoday.com/task/userimages/file/punofudimimoxefuw.pdfIn PDF document text
    • http://salonorganica.ru/upload/files/39415663780.pdfIn PDF document text
    • http://soflocops.org/clients/83264/File/58550127856.pdfIn PDF document text
    • http://gulfcoolcontracting.com/uploads/userfiles/file/file/zutisogijodi.pdfIn PDF document text
    • https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/3tqpip6qko405lakn13vcfns4l/bigarojujixanefitotisiv.pdfIn PDF document text
    • http://akinmedical.com/uploads/file/sorifogegoxiguv.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e5e1a0ac57---gilamixone.pdfIn PDF document text
    • http://boletin.alicantehosteleria.com/lib/ckfinder/userfiles/files/muwufitunoz.pdfIn PDF document text
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/64ffc0f11ec6420967d3c1a807c48815/voxuzodemurejovon.pdfIn PDF document text
    • http://schodylux.pl/userfiles/file/xitivexixes.pdfIn PDF document text
    • https://aslimitada.com/userfiles/file/kupekofidesazobufub.pdfIn PDF document text
    • http://pr-jam.com/ckfinder/userfiles/files/18887930424.pdfIn PDF document text
    • https://cortopolis.ar/userfiles/file/34423369880.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/e2ab263b04da9c6cf9dd2b1874058818/1308924492.pdfIn PDF document text
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/0045dce318c101c45510f9ecbe9d5632/salawexenopig.pdfIn PDF document text
    • http://olversonfamilyreunion.org/clients/5/51/51a48c89da211807e19ed56f8a1a1822/File/lisejorij.pdfIn PDF document text
    • http://boxethai38.com/upload/file/zejugefavaseze.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/ceb46f6ec131239cc63bb185ffa06bfb/41193053741.pdfIn PDF document text
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607234d0d827b---nalukovalo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=paper+chromatography+lab+report+courseheroPDF 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_off0000f749.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF749 10980 bytes
SHA-256: d655095ef320a00e1f66ed6cab37fcf271710bd281d21d01e1bf996a46fc193f
font_01_sfnt_off000110a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110A6 18384 bytes
SHA-256: 03ca87ec7be24fd1d143b531b1503ab4fe244d9bd29da9c62a8ca9a4ef73786d
font_02_sfnt_off00013fa0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13FA0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1